CVE-2026-52761

ModSecurity: Transformation utf8toUnicode produces wrong output on i386 architecture

MEDIUM
5.3
CVSS Score
Published: July 10, 2026 at 09:40 PM UTC
Updated: October 25, 2026 at 03:10 PM UTC
2 products affected across 2 vendorsModsecurityModSecurity

Using ModSecurity by owasp-modsecurity?

Get instant alerts when new vulnerabilities affect ModSecurity - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM5.3
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

3.0.0 ≤ v ≤ 3.0.15
Affected range stops below 3.0.16, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-467

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card