CVE-2025-2559

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

Description

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.

Category

4.9
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.14%
Vendor Advisory redhat.com Vendor Advisory redhat.com
Affected: Red Hat Red Hat Build of Keycloak
Affected: Red Hat Red Hat build of Keycloak 26.0
Affected: Red Hat Red Hat build of Keycloak 26.0
Affected: Red Hat Red Hat build of Keycloak 26.0
Affected: Red Hat Red Hat Single Sign-On 7
Published at:
Updated at:

References

Link Tags
https://access.redhat.com/errata/RHSA-2025:4335 vendor advisory
https://access.redhat.com/errata/RHSA-2025:4336 vendor advisory
https://access.redhat.com/security/cve/CVE-2025-2559 vdb entry
https://bugzilla.redhat.com/show_bug.cgi?id=2353868 issue tracking

Frequently Asked Questions

What is the severity of CVE-2025-2559?
CVE-2025-2559 has been scored as a medium severity vulnerability.
How to fix CVE-2025-2559?
To fix CVE-2025-2559, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2025-2559 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2025-2559 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2025-2559?
CVE-2025-2559 affects Red Hat Red Hat Build of Keycloak, Red Hat Red Hat build of Keycloak 26.0, Red Hat Red Hat build of Keycloak 26.0, Red Hat Red Hat build of Keycloak 26.0, Red Hat Red Hat Single Sign-On 7.
This platform uses data from the NIST NVD, MITRE CVE, MITRE CWE, First.org and CISA KEV but is not endorsed or certified by these entities. CVE is a registred trademark of the MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. CWE is a registred trademark of the MITRE Corporation and the authoritative source of CWE content is MITRE's CWE web site.
© 2025 Under My Watch. All Rights Reserved.