CVE-2025-2559mediumCWE-770

CVE-2025-2559: medium-severity vulnerability in keycloak

Org.keycloak/keycloak-services: jwt token cache exhaustion leading to denial of service (dos) in keycloak

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 4.9epss 0.7%
A flaw was found in Keycloak. When the configuration uses JWT tokens for authentication, the tokens are cached until expiration. If a client uses JWT tokens with an excessively long expiration time, for example, 24 or 48 hours, the cache can grow indefinitely, leading to an OutOfMemoryError. This issue could result in a denial of service condition, preventing legitimate users from accessing the system.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Affected products
keycloakRed Hat · Red Hat Build of KeycloakRed Hat · Red Hat build of Keycloak 26.0Red Hat · Red Hat Single Sign-On 7
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