#VU110697 Integer overflow in FCGI - CVE-2025-40907

Vulnerability identifier: #VU110697

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2025-40907

CWE-ID: CWE-190

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
FCGI
Server applications / Other server solutions

Vendor: Catalyst

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to inclusion of code from libfcgi/fcgiapp.c vulnerable to an integer overflow, as described in #VU107896 (CVE-2025-23016). A remote attacker can send a specially crafted request to the application, trigger memory corruption and execute arbitrary code on the system. 

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability. 

Vulnerable software versions

FCGI: 0.68 - 0.82

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External links
https://github.com/perl-catalyst/FCGI/issues/14

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.