CVE-2026-50559: Authentication/Authorization Bypass via Advanced Path Normalization Vulnerabilities

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-06-19 · updated 2026-10-25
Weakness: CWE-287

Description

Quarkus is a Java framework for building cloud-native applications. Prior to versions 3.37.0, 3.36.3, 3.33.2.1, 3.33.3, 3.27.4.1, 3.27.5, and 3.20.6.2, Quarkus HTTP path-based authorization policies can be bypassed using encoded semicolons (%3B) to smuggle matrix parameters past the security layer, and using encoded slashes (%2F) or backslashes (%5C) to access protected static resources. This is a distinct issue from CVE-2026-39852, which addressed only literal semicolon stripping. Versions 3.37.0, 3.36.3, 3.33.2.1, 3.33.3, 3.27.4.1, 3.27.5, and 3.20.6.2 contain a patch.

Affected products

quarkusio quarkus: before 3.20.6.2; from 3.21.0 before 3.27.4.1; from 3.28.0 before 3.33.2.1; from 3.34.0 before 3.36.3 — fixed in 3.20.6.2, 3.27.4.1, 3.33.2.1, 3.36.3

How to fix

Upgrade to a fixed version: quarkusio quarkus 3.20.6.2, 3.27.4.1, 3.33.2.1, 3.36.3. Check the vendor advisory for mitigations.

References

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