CVE-2026-11800
Org.keycloak:keycloak-services: keycloak: authentication bypass via jwt algorithm confusion
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
CISA's decision points: whether it is exploited, whether attacks can be automated, and how much control an attacker gets. Assessed (SSVC 2.0.3).What do these mean? →
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
A flaw was found in Keycloak. This JWT algorithm confusion vulnerability in the JWT Authorization Grant flow allows an attacker with valid client credentials to bypass signature verification. By forging an assertion, the attacker can create unauthorized access tokens. This enables the attacker to impersonate any federated user linked to the affected Identity Provider, leading to unauthorized access and potential privilege escalation.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- rhbk/keycloak-operator-bundle
Version range not reported
- rhbk/keycloak-rhel9
Version range not reported
- rhbk/keycloak-rhel9-operator
Version range not reported
- Red Hat Red Hat build of Keycloak 26.6.4
Version range not reported
- rhbk/keycloak-rhel9
Version range not reported
- rhbk-openshift-rhel9/rhbk-openshift-rhel9
Version range not reported
- keycloak-services
Version range not reported
- keycloak-services
Version range not reported
- keycloak-services
Version range not reported