How severe is CVE-2026-50559?

CVE-2026-50559 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-50559 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-50559?

CVE-2026-50559 affects Quarkus. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-50559?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-50559 have an EU (EUVD) identifier?

Yes. CVE-2026-50559 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-38084.

When was CVE-2026-50559 published?

CVE-2026-50559 was published on 2026-06-19 and last updated on 2026-07-03.

CVE-2026-50559

CVE-2026-50559 is a high-severity vulnerability in Quarkus with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-38084
Weakness: CWE-287
Affected product: Quarkus
Published: 2026-06-19
Last modified: 2026-07-03

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.

Frequently asked questions

What is CVE-2026-50559?: 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.
How severe is CVE-2026-50559?: CVE-2026-50559 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-50559 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-50559?: CVE-2026-50559 affects Quarkus. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-50559?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-50559 have an EU (EUVD) identifier?: Yes. CVE-2026-50559 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-38084.
When was CVE-2026-50559 published?: CVE-2026-50559 was published on 2026-06-19 and last updated on 2026-07-03.

References

Affected products (1)

cpe:2.3:a:quarkus:quarkus:*:*:*:*:*:*:*:*

More vulnerabilities in Quarkus

CVE-2022-4116 — Critical (CVSS 9.8): A vulnerability was found in quarkus. This security flaw happens in Dev UI Config Editor which is vulnerable to…
CVE-2022-2466 — Critical (CVSS 9.8): It was found that Quarkus 2.10.x does not terminate HTTP requests header context which may lead to unpredictable…
CVE-2024-12225 — Critical (CVSS 9.1): A vulnerability was found in Quarkus in the quarkus-security-webauthn module. The Quarkus WebAuthn module publishes…
CVE-2021-26291 — Critical (CVSS 9.1): Apache Maven will follow repositories that are defined in a dependency’s Project Object Model (pom) which may be…
CVE-2022-0981 — High (CVSS 8.8): A flaw was found in Quarkus. The state and potentially associated permissions can leak from one web request to another…
CVE-2021-29428 — High (CVSS 8.8): In Gradle before version 7.0, on Unix-like systems, the system temporary directory can be created with open permissions…

All CVEs affecting Quarkus →

Other CWE-287 (Improper Authentication) vulnerabilities

CVE-2026-45480 — Critical (CVSS 10.0): Improper authentication in Azure Active Directory allows an unauthorized attacker to elevate privileges over a network.
CVE-2026-46389 — Critical (CVSS 10.0): UDS Identity Config builds the Keycloak configuration image (realm, plugins, theme, truststore, JARs) consumed by UDS…
CVE-2026-10611 — Critical (CVSS 10.0): An authentication bypass vulnerability exists in MISP when LDAP mixed authentication is enabled with OTP enforcement.…
CVE-2026-47280 — Critical (CVSS 10.0): Improper authentication in Azure Resource Manager (ARM) allows an unauthorized attacker to elevate privileges over a…
CVE-2026-42822 — Critical (CVSS 10.0): Improper authentication in Azure Local Disconnected Operations allows an unauthorized attacker to elevate privileges…
CVE-2026-20182 — Critical (CVSS 10.0): May 2026: This security advisory provides the details and fix information for a vulnerability that was discovered and…

Browse all CWE-287 (Improper Authentication) vulnerabilities →