Encoded HTML entities bypass in ModSecurity



Risk Medium
Patch available YES
Number of vulnerabilities 1
CVE-ID CVE-2025-27110
CWE-ID CWE-693
Exploitation vector Network
Public exploit N/A
Vulnerable software
 ModSecurity
Server applications / IDS/IPS systems, Firewalls and proxy servers

Vendor Trustwave

Security Bulletin

This security bulletin contains one medium risk vulnerability.

1) Protection mechanism failure

EUVDB-ID: #VU105981

Risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2025-27110

CWE-ID: CWE-693 - Protection Mechanism Failure

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due to an error when decoding encoded HTML entities. A remote attacker can bypass implemented filtration rules with encoded payload.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

ModSecurity: 3.0.13

CPE2.3 External links

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


Q & A

Can this vulnerability be exploited remotely?

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

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

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



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