The Vdesk Hangup PHP 3 exploit is a remote code execution (RCE) vulnerability that arises from inadequate input validation and output encoding in the Vdesk software. Specifically, the vulnerability exists in the hangup.php script, which is responsible for handling customer support requests.
The vdesk/hangup.php3 exploit specifically targets a cross-site scripting (XSS) and cross-site request forgery (CSRF) vulnerability in older versions of the (such as version 6.0.2 hotfix 3).
Once an open endpoint is identified, the attacker crafts a malicious HTTP GET or POST request. If the script uses an unsanitized variable to terminate a process via the command line, the attacker appends command separators (like ; , && , or | ) followed by their payload. Example of a conceptual malicious request:
If you are seeing frequent, unexplained redirects to /vdesk/hangup.php3 in your environment, it’s worth checking your at /var/log/apm to see if it’s a policy failure or potentially malicious scanning activity. vdesk hangupphp3 exploit
The existence of this overlap indicates that F5 may have released incomplete fixes or that researchers were rediscovering the same underlying input validation weaknesses.
If the hangup functionality is not critical to daily operations, rename or remove the hangup.php3 file from the web root entirely.
Because this exploit targets a legacy system, the absolute best defense is migration. However, if the system must remain online, use the following layered security controls: Immediate Fix: Code Patching The Vdesk Hangup PHP 3 exploit is a
The term "vdesk" suggests integration with Virtual Desktop Infrastructure (VDI) or a specific web-based telephony interface.
: Historical vulnerabilities (like BID 29574 ) existed where the system failed to sanitize user-supplied input in the /vdesk/ directory, potentially allowing remote attackers to execute arbitrary actions.
Starting from version 11.6.0, F5 implemented stricter controls, such as disallowing query parameters in internal URIs like hangup.php3 , to mitigate potential misuse. Administrators are often advised to: Once an open endpoint is identified, the attacker
If you cannot immediately update or replace the software, implement these temporary defensive measures:
Running applications that rely on PHP3 components introduces immense security risks. Modern infrastructures should migrate to supported versions of PHP (8.x+) and replace obsolete software suites with actively maintained alternatives.
The user explicitly clicks the "Log Out" button on an F5 Full Webtop portal.