Medium 5.8Published Jul 10, 2026

CVE-2026-52761ModSecurity: Transformation utf8toUnicode produces wrong output on i386 architecture

Updated under an hour ago (Oct 28, 2026, 8:50 AM ET)

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It affects owasp-modsecurity ModSecurity and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for owasp-modsecurity ModSecurity

Exploited in the last 30 days

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: 5.8 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
Weakness (CWE): CWE-467
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Jul 13, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

owasp-modsecurity ModSecurity owasp_modsecurity:modsecurity (from the name)	from 3.0.0, < 3.0.16	CNA record
owasp modsecurity owasp:modsecurity	from 3.0.0 through 3.0.15	NVD

References

References

https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-qjgm-7gp4-f8qq	x-refsource-confirm, vendor-advisory
https://github.com/owasp-modsecurity/ModSecurity/commit/edcd010814e234d46e2ec55a0f1078ff9d3032e4	x-refsource-misc, patch
https://github.com/owasp-modsecurity/ModSecurity/releases/tag/v3.0.16	x-refsource-misc, product, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.