CVE-2026-39852: Quarkus authorization bypass via semicolon path normalization inconsistency
Quarkus is a Java framework for building cloud-native applications. In versions prior to 3.20.6.1, 3.27.3.1, 3.33.1.1, 3.35.1.1, 3.34.7, and 3.35.2, a path normalization inconsistency between the security layer and the routing layer allows unauthenticated or lower-privileged users to bypass HTTP path-based authorization policies. Quarkus's security layer performs authorization checks on the raw URL path which preserves matrix parameters (semicolons), while RESTEasy Reactive's routing layer strips matrix parameters before matching endpoints. An attacker can append a semicolon and arbitrary text to a request URL (e.g., /api/admin;anything) to bypass policies protecting /api/admin while still routing to the protected endpoint. This issue has been fixed in versions 3.20.6.1, 3.27.3.1, 3.33.1.1, 3.35.1.1, 3.34.7, and 3.35.2.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-39852?
The severity of CVE-2026-39852 is high due to the potential for unauthorized access to protected resources.
How do I fix CVE-2026-39852?
To fix CVE-2026-39852, upgrade to version 3.35.1.1 or later of the affected Quarkus packages.
Which versions of Quarkus are affected by CVE-2026-39852?
CVE-2026-39852 affects Quarkus versions between 3.20.6.1 and 3.34.0, inclusive.
What type of vulnerability is CVE-2026-39852?
CVE-2026-39852 is an authorization bypass vulnerability related to matrix parameters in HTTP requests.
Can unauthorized users exploit CVE-2026-39852?
Yes, unauthorized or lower-privileged users can exploit CVE-2026-39852 to bypass security constraints.