CVE-2026-39852

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. Quarkuss security layer performs authorization checks on the raw URL path which preserves matrix parameters (semicolons), while RESTEasy Reactives 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.

Weakness

The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.

Affected Software

Name	Vendor	Start Version	End Version
Quarkus	Quarkus	*	3.20.6.1 (excluding)
Quarkus	Quarkus	3.21.0 (including)	3.27.3.1 (excluding)
Quarkus	Quarkus	3.28.0 (including)	3.33.1.1 (excluding)
Quarkus	Quarkus	3.34.0 (including)	3.34.7 (excluding)
Quarkus	Quarkus	3.35.0 (including)	3.35.2 (excluding)
Cryostat 4 on RHEL 9	RedHat	cryostat/cryostat-reports-rhel9:4.2.0-9	*
Cryostat 4 on RHEL 9	RedHat	cryostat/cryostat-rhel9:4.2.0-9	*
Cryostat 4 on RHEL 9	RedHat	cryostat/jfr-datasource-rhel9:4.2.0-9	*
HawtIO HawtIO 4.4.0	RedHat	quarkus-vertx-http	*
Red Hat Build of Apache Camel 4.14 for Quarkus 3.27	RedHat	quarkus-vertx-http	*
Red Hat build of Quarkus 3.20.6.SP1	RedHat	quarkus-vertx-http	*
Red Hat build of Quarkus 3.27.3.SP1	RedHat		*
Streams for Apache Kafka 2.9.4	RedHat	quarkus-vertx-http	*

Potential Mitigations

Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) [REF-229] to enforce the roles at the appropriate boundaries.
Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
For example, consider using authorization frameworks such as the JAAS Authorization Framework [REF-233] and the OWASP ESAPI Access Control feature [REF-45].
For web applications, make sure that the access control mechanism is enforced correctly at the server side on every page. Users should not be able to access any unauthorized functionality or information by simply requesting direct access to that page.
One way to do this is to ensure that all pages containing sensitive information are not cached, and that all such pages restrict access to requests that are accompanied by an active and authenticated session token associated with a user who has the required permissions to access that page.

NVD	https://nvd.nist.gov/vuln/detail/CVE-2026-39852
CWE	https://cwe.mitre.org/data/definitions/863.html

Incorrect Authorization

Weakness

Affected Software

Potential Mitigations

References