Exposure of Private Information ('Privacy Violation') in Keycloak - CVE-2026-3911
Published: September 10, 2026
Vulnerability identifier: #VU148929
CSH Severity: Low
CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-3911
CWE-ID: CWE-359
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to disclose sensitive user information.
The vulnerability exists due to improper access control in the UserResource component when accessing a specific administrative endpoint. A remote privileged user can retrieve user attributes configured to be hidden to disclose sensitive user information.
The user must have the view-users role.
Affected software
Keycloak
Red Hat build of Keycloak
Red Hat build of Keycloak
How to mitigate CVE-2026-3911
Install security update from vendor's website.
Keycloak - update to 26.5.6
Red Hat build of Keycloak - update to 26.4.11
Red Hat build of Keycloak - update to 26.4.11