Auth bypass in Red Hat Build Of Keycloak
CVE-2026-93999
A flaw was found in the OIDC protocol implementation of Keycloak, an open-source identity and access management solution. The issue occurs during the token refresh process when the server restores requested audiences from stored client IDs. Keycloak fails to verify if the target audience client is still enabled before issuing a new access token. This allows an application with an existing refresh token to continue obtaining valid access tokens for a disabled client, potentially bypassing administrative access controls for resource servers that rely on offline JWT validation.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.2 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.002 (13.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 14th percentile — 13.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
Weakness classification (CWE)
References
- access.redhat.com/security/cve/CVE-2026-93999 (vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking)
Frequently asked questions
- What is CVE-2026-93999?
- CVE-2026-93999 is a medium-severity vulnerability in Red Hat Build Of Keycloak, classified under Missing Authorization. CVSS score: 4.2/10. Published 2026-09-19.
- How severe is CVE-2026-93999?
- Medium severity. CVSS v3 base score is 4.2 out of 10.