Bug 2499332

Summary:	CVE-2026-52761 mod_security: ModSecurity: Web Application Firewall rules bypass due to incorrect UTF-8 to Unicode transformation [fedora-all]
Product:	[Fedora] Fedora	Reporter:	Ganesh <gnaik>
Component:	mod_security	Assignee:	Luboš Uhliarik <luhliari>
Status:	CLOSED NOTABUG	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	rawhide	CC:	jorton, luhliari
Target Milestone:	---	Keywords:	Security, SecurityTracking
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:	{"flaws": ["6ba5f4d3-7c70-45b2-b094-538985e2cb5b"]}
Fixed In Version:		Doc Type:	---
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2026-07-22 19:39:35 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	2499254

Description Ganesh 2026-07-11 07:23:47 UTC

Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

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.

Comment 1 Luboš Uhliarik 2026-07-22 19:39:35 UTC

Does NOT affect mod_security v2 which is present in Fedora.