High [CVE-2025-11561] Sssd: sssd default kerberos configuration allows privilege escalation on ad-joined linux systems

A flaw was found in the integration of Active Directory and the System Security Services Daemon (SSSD) on Linux systems. In default configurations, the Kerberos local authentication plugin (sssd_krb5_localauth_plugin) is enabled, but a fallback to the an2ln plugin is possible.

This fallback allows an attacker with permission to modify certain AD attributes (such as userPrincipalName or samAccountName) to impersonate privileged users, potentially resulting in unauthorized access or privilege escalation on domain-joined Linux hosts.

The Red Hat Product Security team has assessed this issue as High severity for domain-joined Linux systems using default SSSD configurations. This could lead to unauthorized access or elevated privileges on affected Linux hosts.

Administrators are advised to review and apply recommended hardening configurations to mitigate this behavior. Red Hat severity: Important — CVSS 8.8 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).

Weakness: CWE-269.

Affected products named by the advisory: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 7 Extended Lifecycle Support; Red Hat Enterprise Linux 8.2 Advanced Update Support; Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support; and 23 more.