Keycloak: Revoked Tokens Can Remain Active When Both Realm-Level and Client-Level `notBefore` Revocation Policies are Configured

Description

A flaw was found in Keycloak. When both realm-level and client-level notBefore revocation policies are configured, Keycloak's OpenID Connect (OIDC) Introspection feature fails to properly honor the realm-level policy. This allows tokens that should have been revoked to remain active, potentially leading to unauthorized access or continued session validity. This could impact the security of systems utilizing Keycloak for identity and access management.

Basic information

Type
reviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
Source code
Browse source ↗
Published (advisory)
2026-05-19 09:31:21 UTC
Updated
2026-06-11 00:33:07 UTC
GitHub reviewed
2026-06-04 17:30:58 UTC
NVD published
2026-05-19

EPSS Score

Score Percentile
0.01% 1.11%

CVSS Scores

Base score Version Severity Vector
5.4 3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.

Identifiers

CWEs

CWE id Name
CWE-303 Incorrect Implementation of Authentication Algorithm

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
maven org.keycloak:keycloak-services <= 26.6.2

References

cvelogic Threat Intelligence