CVE-2025-23016: 
CBL Mariner vulnerability analysis and mitigation

FastCGI fcgi2 (aka fcgi) versions 2.x through 2.4.4 contain an integer overflow vulnerability that can lead to a heap-based buffer overflow. The vulnerability exists in the ReadParams function within fcgiapp.c and is triggered when processing nameLen or valueLen values in data sent to the IPC socket. The vulnerability was discovered and disclosed on January 10, 2025 (NVD, GitHub Issue).

The vulnerability occurs in the ReadParams function of fcgiapp.c when processing nameLen and valueLen parameters. When these values are read from the input data fed to fcgi's IPC socket, an integer overflow can occur during the calculation of nameLen + valueLen. This overflow results in allocating a buffer smaller than required through malloc(), leading to a heap-based buffer overflow during subsequent operations. The vulnerability has been assigned a CVSS v3.1 base score of 9.3 CRITICAL with vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H (NVD).

The vulnerability could potentially lead to remote code execution, particularly in embedded equipment with limited system protections such as those lacking ASLR or NX bits. The impact could be especially severe if the socket is exposed due to misconfiguration or if combined with other vulnerabilities like SSRF within the web application (GitHub Issue).

Red Hat Product Security has determined that this vulnerability does not affect any currently supported Red Hat product, though this assessment may evolve based on further analysis (Red Hat). No specific patches or workarounds have been publicly documented at the time of this report.