CVE-2026-37982

Keycloak: org.keycloak.authentication: keycloak: unauthorized account takeover via webauthn token replay

Published May 19, 2026 CVSS 3.1 · 6.8 Medium EPSS < 1% KEV · Not listed
Description
A flaw was found in Keycloak. This authentication vulnerability allows a remote attacker to replay `ExecuteActionsActionToken` tokens within Keycloak's WebAuthn (Web Authentication) flow. By intercepting an execute-actions email link, an attacker can register their own authenticator to a victim's account. This leads to unauthorized enrollment of a hardware-backed credential, enabling persistent account takeover.

Remediation

Vendor Workaround

To mitigate this issue, consider disabling WebAuthn required actions in Keycloak if they are not essential for your deployment. This will prevent the vulnerable token replay mechanism from being exploited. Consult Keycloak documentation for specific configuration steps to disable WebAuthn required actions. Note that applying configuration changes may require a service restart and could impact functionality relying on WebAuthn registration.

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-w4p5-rfh6-cwrv Keycloak: Unauthorized account takeover via WebAuthn token replay
History
Type Values Removed Values Added
CPEs cpe:2.3:a:redhat:build_of_keycloak:*:*:*:*:*:*:*:*
Type Values Removed Values Added
CPEs cpe:/a:redhat:build_keycloak: cpe:/a:redhat:build_keycloak:26.4::el9
References
Type Values Removed Values Added
Weaknesses CWE-1025
CWE-602
Type Values Removed Values Added
First Time appeared Redhat build Of Keycloak
Vendors & Products Redhat build Of Keycloak
Type Values Removed Values Added
Weaknesses CWE-294
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Weaknesses CWE-1025
CWE-602
Type Values Removed Values Added
Description A flaw was found in Keycloak. This authentication vulnerability allows a remote attacker to replay `ExecuteActionsActionToken` tokens within Keycloak's WebAuthn (Web Authentication) flow. By intercepting an execute-actions email link, an attacker can register their own authenticator to a victim's account. This leads to unauthorized enrollment of a hardware-backed credential, enabling persistent account takeover.
Title Keycloak: org.keycloak.authentication: keycloak: unauthorized account takeover via webauthn token replay
First Time appeared Redhat
Redhat build Keycloak
CPEs cpe:/a:redhat:build_keycloak:
Vendors & Products Redhat
Redhat build Keycloak
References
Metrics cvssV3_1

{'score': 6.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
redhat
Published
Updated
Oct 29, 2026, 9:29 AM
Reserved
Apr 6, 2026, 7:48 AM
Status
Modified
Published
May 19, 2026, 12:16 PM
Modified
Oct 29, 2026, 10:17 AM
Severity
Moderate
Public date
May 19, 2026, 12:00 AM