CVE-2026-45074
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 7.1.0 until 7.4.12 and 8.0.12, Cas2Handler builds the CAS service parameter from Request::getSchemeAndHttpHost(), which reflects an attacker-controlled Host header when framework.trusted_hosts is not configured; an attacker controlling another application registered with the same CAS server can replay a victim ticket against the Symfony application and authenticate as the victim. This issue is fixed in versions 7.4.12 and 8.0.12.
No public exploitation has been reported so far. No distribution fix is listed yet; apply vendor mitigations and monitor.
Recommended action: Track your distribution's security tracker and apply the fix as soon as it ships.
Severity metrics
CVSS 4.0 : 7.6 HIGH · CVSS 3.1 : 8.1 HIGH
Vector: AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
Affected & fixed versions by distribution
Versions are the native distribution strings (backport-aware): RHEL/Debian/SUSE backport fixes, so compare with the distro version comparator (dpkg / rpm / vercmp), not the upstream version.
No affected package in the tracked watchlist yet (Debian, Ubuntu, Arch, SUSE, Red Hat...). Triage may still be pending.