FCGI versions 0.44 through 0.82, for Perl, include a vulnerable version of the FastCGI fcgi2 (aka fcgi) library. The included FastCGI library is affected by CVE-2025-23016, causing an integer overflow (and resultant heap-based buffer overflow) via crafted nameLen or valueLen values in data to the IPC socket. This occurs in ReadParams in fcgiapp.c.

• http://www.openwall.com/lists/oss-security/2025/04/23/4
• https://github.com/FastCGI-Archives/fcgi2/issues/67
• https://github.com/FastCGI-Archives/fcgi2/releases/tag/2.4.5
• https://github.com/perl-catalyst/FCGI/issues/14
• https://patch-diff.githubusercontent.com/raw/FastCGI-Archives/fcgi2/pull/74.patch
• https://www.synacktiv.com/en/publications/cve-2025-23016-exploiting-the-fastcgi-library