Medium severity · published Oct 30, 2026
CVE-2026-118959
Keycloak-services: keycloak-services: required actions bypassed via kc_action parameter
New
5.4
CVSS
–
EPSS
No
On KEV
Description
A flaw was found in the required action provider mechanism of Keycloak. The issue occurs when an authorization request includes the kc_action query parameter set to a mandatory action already assigned to the user, such as profile verification or terms and conditions. Due to incorrect handling of application-initiated actions, Keycloak may skip these mandatory challenges and issue an authorization code. This can allow a user to bypass administrative requirements and gain access to the application without completing necessary profile updates or agreeing to terms.
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?
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-2026-118959
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-118959
vdb-entry
https://access.redhat.com/security/cve/CVE-2026-118959
issue-tracking
https://bugzilla.redhat.com/show_bug.cgi?id=2563288
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