CVE-2025-40907
FCGI versions 0.44 through 0.82, for Perl, include a vulnerable version of the FastCGI fcgi2 (aka fcgi) library.
Does this matter?
Lower severity and a low EPSS score (0.68%). Track it; it rarely justifies an emergency change on its own.
Description
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.
- CVSS 3.1
- 5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- EPSS
- 0.68% probability · 52th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-122, CWE-190
- Affected
- fastcgi/fcgi
- Source
- 9b29abf9-4ab0-4765-b253-1875cd9b441e
EPSS 0.7% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.openwall.com/lists/oss-security/2025/04/23/4Mailing List, Third Party Advisory
- https://github.com/FastCGI-Archives/fcgi2/issues/67Exploit, Issue Tracking
- https://github.com/FastCGI-Archives/fcgi2/releases/tag/2.4.5Release Notes
- https://github.com/perl-catalyst/FCGI/issues/14Exploit, Issue Tracking
- https://patch-diff.githubusercontent.com/raw/FastCGI-Archives/fcgi2/pull/74.patchPatch
- https://www.synacktiv.com/en/publications/cve-2025-23016-exploiting-the-fastcgi-libraryExploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.