CVE-2026-42268

ModSecurity: Unsigned integer underflow in @verifySSN / @verifyCPF / @verifySVNR operators

Published: May 12, 2026Updated: May 14, 2026 Sources: CVE List NVDCWE-191

7.5HIGH

Description

ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. From 3.0.0 to before 3.0.15, there is an unhandled exception (std::out_of_range) caused by unsigned integer underflow in libmodsecurity3 if the user (administrator) uses a rule any of @verifySSN, @verifyCPF, or @verifySVNR. This vulnerability is fixed in 3.0.15.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-191 CWE-248

Affected Products

owasp-modsecurity

oss-projectaka modsecurity, mod_security

ModSecurityOn-prem

Networking Infrastructure / firewall

owasp

oss-project·USaka modsecurity, owasp modsecurity core rule set, modsecurity-crs

modsecurityMixed

Networking Infrastructure / firewall

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Initial Access

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References

https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-vwr3-7x7g-7p9w

github.com

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