FUDForum 3.0.9 admsession.php User-Agent Stored cross site scripting

Summaryinfo

A vulnerability classified as problematic has been found in FUDForum 3.0.9. The affected element is an unknown function of the file admsession.php. Performing a manipulation of the argument User-Agent as part of HTTP Header results in cross site scripting (Stored). This vulnerability is known as CVE-2019-18873. Remote exploitation of the attack is possible. Furthermore, an exploit is available.

Detailsinfo

A vulnerability classified as problematic has been found in FUDForum 3.0.9 (Forum Software). This affects some unknown processing of the file admsession.php. The manipulation of the argument User-Agent as part of a HTTP Header leads to a cross site scripting vulnerability (Stored). CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity. The summary by CVE is:

FUDForum 3.0.9 is vulnerable to Stored XSS via the User-Agent HTTP header. This may result in remote code execution. An attacker can use a user account to fully compromise the system via a GET request. When the admin visits user information under "User Manager" in the control panel, the payload will execute. This will allow for PHP files to be written to the web root, and for code to execute on the remote server. The problem is in admsession.php and admuser.php.

The weakness was published 11/12/2019. This vulnerability is uniquely identified as CVE-2019-18873 since 11/12/2019. It is possible to initiate the attack remotely. Required for exploitation is a authentication. It demands that the victim is doing some kind of user interaction. Technical details and a public exploit are known. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

A public exploit has been developed by liquidsky in Javascript and been published before and not just after the advisory. The exploit is shared for download at github.com. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 17 days. During that time the estimated underground price was around $0-$5k. By approaching the search of inurl:admsession.php it is possible to find vulnerable targets with Google Hacking.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Exploit-DB (47650). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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Type

• Forum Software

Name

• FUDForum

Version

• 3.0.9

CPE 2.3info

• 🔍

CPE 2.2info

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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