Medium severity · published Mar 25, 2025
CVE-2025-2559
Org.keycloak/keycloak-services: jwt token cache exhaustion leading to denial of service (dos) in keycloak
4.9
CVSS
0.7%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 53% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RH
Red Hat Single Sign-On 7 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat build of Keycloak 26.0 · Red Hat
All versions, or not specified · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-2559
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-2559
access.redhat.com
https://access.redhat.com/errata/RHSA-2025:4335
access.redhat.com
https://access.redhat.com/errata/RHSA-2025:4336
access.redhat.com
https://access.redhat.com/security/cve/CVE-2025-2559
bugzilla.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2353868
github.com
https://github.com/keycloak/keycloak/commit/a10c8119d4452b866b90a9019b2cc159919276ca
github.com
https://github.com/keycloak/keycloak/issues/38576
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