Authentication interruption via unbounded JWT token caching
Published Mar 25, 2025 · Updated May 6, 2026
Resource exhaustion in Keycloak 23.0.0 through 26.0.10 and 26.1.0 through 26.1.4 allows remote authenticated users to interrupt service. JWTClientValidator derives each single-use-cache entry's lifetime from the signed token's exp claim without enforcing a server-controlled maximum. A trusted client using Signed JWT or Signed JWT with Client Secret can submit many long-lived assertions, retaining cache entries until an OutOfMemoryError interrupts authentication.
Summary
What happened
Resource exhaustion in Keycloak 23.0.0 through 26.0.10 and 26.1.0 through 26.1.4 allows remote authenticated users to interrupt service. JWTClientValidator derives each single-use-cache entry's lifetime from the signed token's exp claim without enforcing a server-controlled maximum. A trusted client using Signed JWT or Signed JWT with Client Secret can submit many long-lived assertions, retaining cache entries until an OutOfMemoryError interrupts authentication.
The record
- CVE
- CVE-2025-2559
- Published
- Mar 25, 2025
- Updated
- May 6, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat Single Sign-On 7
- Classifications
- CWE-770, T1499.003
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Mar 25, 2025CVE publishedPublication date reported by the CVE source.
- May 6, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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