Vulnerability · Published Feb 25, 2025 · Assigned by GitHub_M

CVE-2025-27110Libmodsecurity3 has possible bypass of encoded HTML entities

High 7.9

In plain English

A high-severity security flaw in ModSecurity from owasp-modsecurity. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)7.9High

Exploit odds (30 days)0.5%top 58.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

Libmodsecurity is one component of the ModSecurity v3 project. The library codebase serves as an interface to ModSecurity Connectors taking in web traffic and applying traditional ModSecurity processing. A bug that exists only in Libmodsecurity3 version 3.0.13 means that, in 3.0.13, Libmodsecurity3 can't decode encoded HTML entities if they contains leading zeroes. Version 3.0.14 contains a fix. No known workarounds are available.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:13	modsecurity	3.0.14-1	DEBIAN-CVE-2025-27110
Debian:14	modsecurity	3.0.14-1	DEBIAN-CVE-2025-27110
Ubuntu:22.04:LTS	modsecurity	no fix listed	UBUNTU-CVE-2025-27110
Ubuntu:24.04:LTS	modsecurity	no fix listed	UBUNTU-CVE-2025-27110
Ubuntu:25.10	modsecurity	no fix listed	UBUNTU-CVE-2025-27110
Ubuntu:26.04:LTS	modsecurity	no fix listed	UBUNTU-CVE-2025-27110
Ubuntu:26.10	modsecurity	no fix listed	UBUNTU-CVE-2025-27110

Affected products (as reported)

Vendor	Product	Versions
owasp-modsecurity	ModSecurity	= 3.0.13

Weakness: CWE-172 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H

References

https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-42w7-rmv5-4x2j x_refsource_CONFIRM
https://github.com/owasp-modsecurity/ModSecurity/issues/3340 x_refsource_MISC