Medium severity · published May 19, 2026
CVE-2026-37982
Keycloak: org.keycloak.authentication: keycloak: unauthorized account takeover via webauthn token replay
6.8
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RH
Red Hat build of Keycloak 26.4 · Red Hat
All versions, or not specified · source: vendor
BO
Build OF Keycloak · Redhat
26.4 before 26.4.12 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-37982
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-37982
Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:19596
Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:19597
Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-37982
Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2455329
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