Gnuboard5 - Redirect Creation (CVE-2024-37656)

CVE-2024-37656 is an open redirect vulnerability in gnuboard5 version 5.5.16, where insufficient URL parameter verification in bbs/logout.php allows remote attackers to redirect users to malicious sites. This flaw can be exploited to steal sensitive information through phishing attacks or social engineering.

CrowdSec has been tracking this vulnerability and its exploits since 26th of November 2025.

CrowdSec network data shows that most actors exploiting CVE-2024-37656 rely on broad, untargeted scans with minimal filtering. The activity is largely automated and opportunistic in nature. Telemetry from the CrowdSec network also shows that exploitation activity for CVE-2024-37656 remains steady week-over-week. Attack volumes are consistent with long-term trends, indicating sustained interest from threat actors. CVE-2024-37656 continues to be an active part of the threat landscape and will likely remain this way for the forseeable future.

Attackers exploit this vulnerability by sending requests to /bbs/logout.php or /gnuboard5/bbs/logout.php with a crafted url parameter, causing users to be redirected to attacker-controlled domains.