CVE-2026-52761
ModSecurity: Transformation utf8toUnicode produces wrong output on i386 architecture
5.3
MEDIUM
CVSS 3.1
EPSS 0.41%
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.
How to fix CVE-2026-52761
To remediate CVE-2026-52761, upgrade the affected package to a fixed version below.
- —upgrade to 3.0.16 or later
- —upgrade to 3.0.16 or later
- —no fix listed
Is CVE-2026-52761 being exploited?
Low — EPSS is 0.4%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- >= 3.0.0, < 3.0.16
- >= 3.0.0, < 3.0.16
- from 0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |