Resource exhaustion in Red Hat Build Of Keycloak

CVE-2025-2559

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.

EPSS: 0.007 (47.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.9 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-2559?
CVE-2025-2559 is a medium-severity vulnerability in Red Hat Build Of Keycloak, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 4.9/10. Published 2025-03-25.
How severe is CVE-2025-2559?
Medium severity. CVSS v3 base score is 4.9 out of 10.