CVE-2026-54733 | microsoft o365-moodle up to 4.5.5/5.0.4/5.1.0 Teams SSO Endpoint sso_login.php upn improper authentication (WID-SEC-2026-2400)

A vulnerability, which was classified as critical, has been found in microsoft o365-moodle up to 4.5.5/5.0.4/5.1.0. This affects an unknown function of the file sso_login.php of the component Teams SSO Endpoint. The manipulation of the argument upn leads to improper authentication. This vulnerability is documented as CVE-2026-54733. The attack can be initiated remotely. There is not any exploit available.