CVE-2026-18218 Keycloak-services: keycloak-services: client not-before revocation ignored when realm not-before is older but nonzero
Attackers can bypass client-specific token revocation policies if a realm-level policy exists, allowing continued access to user information with invalidated tokens.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-18218?
CVE-2026-18218 is a medium-severity vulnerability in Redhat Build of Keycloak, published on 31 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A flaw was found in the TokenManager component of the Keycloak identity management service. When an administrator attempts to revoke tokens for a specific application (client) using a "not-before" policy, the revocation may be silently ignored if the overall security realm already has an older, non-zero revocation policy in place. This issue can allow previously issued tokens to remain valid for refreshing sessions and accessing user information even after an administrator has attempted to invalidate them. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Weakness: CWE-862
Which versions are affected by CVE-2026-18218?
1 open source package ship an affected version, including keycloak. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
keycloak Bitnami | All versions | 26.7.3 |
Products include Redhat Build of Keycloak.
How do I fix CVE-2026-18218?
Upgrade keycloak to 26.7.3 or later.
Is CVE-2026-18218 being exploited?
There is no known exploitation of CVE-2026-18218 in the wild and no public exploit code.
Other vulnerabilities in Redhat Build of Keycloak
- CVE-2026-15572 Keycloak-services: keycloak-services: dcr protocol mapper type-swap policy bypass allows privilege escalation
- CVE-2026-3047 Keycloak SAML Broken has Authentication Bypass by Primary Weakness
- CVE-2026-15573 Keycloak-services: keycloak-services: authorization bypass via unnormalized uri matching in pathmatcher
- CVE-2026-16102 Keycloak-services: keycloak-services: default dcr policy allows role forgery via user property mappers
- CVE-2026-1609 Org.keycloak/keycloak-quarkus-server: keycloak: unauthorized access via jwt authorization grant with disabled users
Sources
Also known as BIT-keycloak-2026-18218, CLEANSTART-2026-PI18525, GHSA-vhxw-j6h3-48jm.