Vulnerability Details CVE-2025-40907
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.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.001
EPSS Ranking 29.7%
CVSS Severity
CVSS v3 Score 5.3
References
- 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