Critical [CVE-2025-4404] Freeipa: idm: privilege escalation from host to domain admin in freeipa

A privilege escalation from host to domain vulnerability was found in the FreeIPA project. The FreeIPA package fails to validate the uniqueness of the `krbCanonicalName` for the admin account by default, allowing users to create services with the same canonical name as the REALM admin.

When a successful attack happens, the user can retrieve a Kerberos ticket in the name of this service, containing the admin@REALM credential. This flaw allows an attacker to perform administrative tasks over the REALM, leading to access to sensitive data and sensitive data exfiltration.

For an attack to be successfully executed, the Kerberos ticket needs to be requested with the PAC information. This vulnerability is marked as Important rather than a Moderate one because it allows a local or authenticated attacker to escalate privileges from host-level to full domain-level administrative access within a FreeIPA-managed environment.

By exploiting the lack of uniqueness enforcement on the krbCanonicalName attribute, an attacker can craft a principal with the same canonical name as the domain admin (e.g., admin@REALM) and obtain a Kerberos service ticket that includes PAC (Privilege Attribute Certificate) data.

This results in the impersonation of the admin identity, granting unrestricted access to sensitive systems and data.