Medium severity · published Oct 6, 2026
CVE-2026-105305
Keycloak-services: keycloak-services: device authorization grant bypasses per-client minimum.acr.value enforcement
5.4
CVSS
0.2%
EPSS
No
On KEV
Description
A flaw was found in the OIDC implementation of Keycloak, specifically within the Device Authorization Grant flow. This component allows devices with limited input capabilities to obtain security tokens. The issue occurs because the flow fails to check the minimum authentication level required by a client configuration. This allows an attacker who has stolen a user's password to bypass mandatory multi-factor authentication and gain unauthorized access to the Keycloak Admin REST API.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 8% 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 · Red Hat
All versions, or not specified · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-105305
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-105305
vdb-entry
https://access.redhat.com/security/cve/CVE-2026-105305
issue-tracking
https://bugzilla.redhat.com/show_bug.cgi?id=2545801
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