CVE-2026-52761: CWE-467: Use of sizeof() on a Pointer Type in owasp-modsecurity ModSecurity
ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. From 3.0.0 through 3.0.15, the t:utf8toUnicode transformation in src/actions/transformations/utf8_to_unicode.cc produces wrong output on i386 architecture because snprintf uses sizeof on a char pointer rather than the length of the unicode buffer, allowing rules that use this transformation to be bypassed on i386 architecture. This issue is fixed in version 3.0.16.
AI Analysis
Technical Summary
ModSecurity, an open source web application firewall, contains a vulnerability (CWE-467) in its t:utf8toUnicode transformation function within versions 3.0.0 to 3.0.15. On i386 architecture, the function incorrectly calculates buffer size by using sizeof on a char pointer rather than the unicode buffer length, causing snprintf to produce wrong output. This flaw enables bypassing of rules that rely on this transformation. The vulnerability is resolved in version 3.0.16.
Potential Impact
This vulnerability allows attackers to bypass security rules that use the t:utf8toUnicode transformation on affected ModSecurity versions running on i386 architecture. The integrity of rule enforcement is compromised, potentially allowing malicious input to evade detection or blocking. There is no direct impact on confidentiality or availability reported.
Mitigation Recommendations
Upgrade ModSecurity to version 3.0.16 or later, where this issue is fixed. Patch status is confirmed by the version fix information. No other mitigation is indicated.
CVE-2026-52761: CWE-467: Use of sizeof() on a Pointer Type in owasp-modsecurity ModSecurity
Description
ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. From 3.0.0 through 3.0.15, the t:utf8toUnicode transformation in src/actions/transformations/utf8_to_unicode.cc produces wrong output on i386 architecture because snprintf uses sizeof on a char pointer rather than the length of the unicode buffer, allowing rules that use this transformation to be bypassed on i386 architecture. This issue is fixed in version 3.0.16.
CVSS v3.1
Score 5.8medium
Affected software
pkg:github/owasp-modsecurity/ModSecurityRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
ModSecurity, an open source web application firewall, contains a vulnerability (CWE-467) in its t:utf8toUnicode transformation function within versions 3.0.0 to 3.0.15. On i386 architecture, the function incorrectly calculates buffer size by using sizeof on a char pointer rather than the unicode buffer length, causing snprintf to produce wrong output. This flaw enables bypassing of rules that rely on this transformation. The vulnerability is resolved in version 3.0.16.
Potential Impact
This vulnerability allows attackers to bypass security rules that use the t:utf8toUnicode transformation on affected ModSecurity versions running on i386 architecture. The integrity of rule enforcement is compromised, potentially allowing malicious input to evade detection or blocking. There is no direct impact on confidentiality or availability reported.
Mitigation Recommendations
Upgrade ModSecurity to version 3.0.16 or later, where this issue is fixed. Patch status is confirmed by the version fix information. No other mitigation is indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-08T17:13:43.063Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a516c2c68715ace434381f8
Added to database: 07/10/2026, 22:03:24 UTC
Last enriched: 07/18/2026, 15:45:15 UTC
Last updated: 08/23/2026, 10:52:09 UTC
Views: 55
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