CVE-2026-37979
mediumpriority · track · 0EPSS 0.004 · 30 %ileDEEUUSEPSS · scored 2026-10-27
A flaw was found in Keycloak. This access control vulnerability in Keycloak's OpenID Connect (OIDC) token introspection endpoint allows a confidential client to bypass audience restrictions. An attacker-controlled client with valid credentials can retrieve sensitive token claims intended for other resource servers, compromising the confidentiality of lightweight access tokens. This issue can be exploited remotely by any confidential client in the realm with valid credentials.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (8)
Products and version ranges known to be affected.
advisories (3)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-1612Keycloak: Mehrere SchwachstellenDeutsch2026-05-19csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Keycloak ausnutzen, um Informationen offenzulegen, Daten zu manipulieren, Sicherheitsvorkehrungen zu umgehen und einen Denial of Service zu verursachen.
- GHSA-4x37-hw65-52w8Keycloak: Information disclosure via OIDC token introspection endpoint audience bypass2026-05-19ghsa · osvUS
A flaw was found in Keycloak. This access control vulnerability in Keycloak's OpenID Connect (OIDC) token introspection endpoint allows a confidential client to bypass audience restrictions. An attacker-controlled client with valid credentials can retrieve sensitive token claims intended for other resource servers, compromising the confidentiality of lightweight access tokens. This issue can be exploited remotely by any confidential client in the realm with valid credentials.
- BIT-keycloak-2026-37979Keycloak: keycloak: information disclosure via oidc token introspection endpoint audience bypass2026-08-25vendor · osvUS
A flaw was found in Keycloak. This access control vulnerability in Keycloak's OpenID Connect (OIDC) token introspection endpoint allows a confidential client to bypass audience restrictions. An attacker-controlled client with valid credentials can retrieve sensitive token claims intended for other resource servers, compromising the confidentiality of lightweight access tokens. This issue can be exploited remotely by any confidential client in the realm with valid credentials.
also known as (5)
Other names and identifiers for this entity.
sources
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references (10)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2026-37979cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2026-37979cnnvd
- https://access.redhat.com/errata/RHSA-2026:19596enisa_euvd
- https://access.redhat.com/errata/RHSA-2026:19597enisa_euvd
- https://access.redhat.com/security/cve/CVE-2026-37979enisa_euvd
- https://bugzilla.redhat.com/show_bug.cgi?id=2455328enisa_euvd
- https://access.redhat.com/errata/RHSA-2026:19596Vendor Advisorynvd
- https://access.redhat.com/errata/RHSA-2026:19597Vendor Advisorynvd
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