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TI-2025-02228 Aliases CVE-2025-2559GHSA-2935-2wfm-hhpv

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

Priority LOW 24CWE-770Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 2 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-770.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00703 53rd percentileScored 2026-11-07
Fix Partial keycloak: 26.0.11, 26.1.5Red Hat: 2 advisoriesRed Hat: 2 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
—keycloak23.0.0 to before 26.0.11; 26.1.0 to before 26.1.526.0.11, 26.1.5Patch availableCNA
Red HatRed Hat Build of Keycloak——Not affectedCNA
Red HatRed Hat build of Keycloak 26.0—26.0.11-2Patch availableCNA
Red HatRed Hat build of Keycloak 26.0—26.0-12Patch availableCNA
Red HatRed Hat build of Keycloak 26.0—26.0-13Patch availableCNA
Red HatRed Hat Single Sign-On 7——No fix listedCNA
—org.keycloak:keycloak-services (Maven)up to 26.1.4—No fix listedGHSA-2935-2wfm-hhpv
  • keycloak Vendor— Affected 23.0.0 to before 26.0.11; 26.1.0 to before 26.1.5 Fixed in 26.0.11, 26.1.5 Patch available CNA
  • Red Hat Build of Keycloak VendorRed Hat Affected — Fixed in — Not affected CNA
  • Red Hat build of Keycloak 26.0 VendorRed Hat Affected — Fixed in 26.0.11-2 Patch available CNA
  • Red Hat build of Keycloak 26.0 VendorRed Hat Affected — Fixed in 26.0-12 Patch available CNA
  • Red Hat build of Keycloak 26.0 VendorRed Hat Affected — Fixed in 26.0-13 Patch available CNA
  • Red Hat Single Sign-On 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
  • org.keycloak:keycloak-services (Maven) Vendor— Affected up to 26.1.4 Fixed in — No fix listed GHSA-2935-2wfm-hhpv

CPE names CNA · 3

CPEVersionsRoleVendor
cpe:/a:redhat:build_keycloak:26.026.0—Red Hat
cpe:/a:redhat:build_keycloak:26.0::el926.0—Red Hat
cpe:/a:redhat:red_hat_single_sign_on:77—Red Hat
  • cpe:/a:redhat:build_keycloak:26.0 Versions 26.0 — ·Red Hat
  • cpe:/a:redhat:build_keycloak:26.0::el9 Versions 26.0 — ·Red Hat
  • cpe:/a:redhat:red_hat_single_sign_on:7 Versions 7 — ·Red Hat

Remediation

  • Fix · CNA keycloak Fixed in 26.0.11, 26.1.5

Red Hat 2 advisories

  • RHSA-2025:4335 Released 2025-04-29 · Red Hat rating Important
    Red Hat build of Keycloak 26.0.11 Images Update
    • Red Hat build of Keycloak 26.0 rhbk/keycloak-operator-bundle, rhbk/keycloak-rhel9, rhbk/keycloak-rhel9-operator
  • RHSA-2025:4336 Released 2025-04-29 · Red Hat rating Important
    Red Hat build of Keycloak 26.0.11 Update
    • Red Hat Build of Keycloak

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Single Sign-On 7AffectedNo fix yet: Fix deferred
Red Hat Build of KeycloakFixed RHSA-2025:4336
Red Hat build of Keycloak 26.0Fixed RHSA-2025:4335

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-2559
  2. 2026-10-03 Alias added: GHSA-2935-2wfm-hhpv

References

Advisory 3

Other 5

  • TI-2019-15875 Protection mechanism failure in Jenkins Pipeline: Groovy Plugin KEVCVSS 3.1CRITICAL 9.9
  • TI-2019-15874 Protection mechanism failure in Jenkins Script Security Plugin KEVCVSS 3.1CRITICAL 9.9
  • TI-2019-08259 Underflow in PHP-FPM can lead to RCE KEVCVSS 3.1CRITICAL 9.8
  • TI-2019-05363 Code injection in Elastic Kibana KEVCVSS 3.1CRITICAL 10.0
  • TI-2019-03949 Out-of-bounds write in ESXi and Horizon DaaS KEVCVSS 3.1CRITICAL 9.8
  • TI-2018-16080 A code execution vulnerability exists in the Stapler web framework used by Jenkins 2.153… KEVCVSS 3.1CRITICAL 9.8
See all 7413 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences