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CVE-2026-118030EUVD-2026-112640GHSA-HX7P-FFJF-VX59

Keycloak-services: keycloak-services: hotp race condition allows single otp code reuse across concurrent logins

Published
Last modified
published
Not listed in CISA KEV
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: no
  • Technical impact: partial

Summary

Keycloak's keycloak-services component, which provides identity and access management, is affected when HOTP (one-time password) authentication is used. An attacker who already has a user's password could use a race condition to reuse a single one-time code for multiple simultaneous logins, bypassing the intended second factor.

Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.

Read the original description

A flaw was found in the HOTP authentication mechanism of the keycloak-services component, which provides identity and access management services. The issue occurs because the system validates a one-time password and updates its internal counter in two separate steps without proper locking. An attacker with a users password could exploit this timing gap to use a single one-time code to log in multiple times simultaneously.

Timeline

  1. CVE published
  2. First seen by cve.now
  3. CISA SSVC assessment

    Exploitation: none · Automatable: no · Technical impact: partial

  4. Record last updated

Affected versions

  • keycloak-services

    Version range not reported

  • rhbk/keycloak-rhel9

    Version range not reported

  • keycloak-services

    Version range not reported

References 2

access.redhat.com

bugzilla.redhat.com