GHSA-4M6C-649P-F6GF Serendipity has a Host Header Injection allows authentication cookie scoping to attacker-controlled domain in functions_config.inc.php

Summary The serendipitysetCookie function uses $SERVER'HTTPHOST' without validation as the domain parameter of setcookie. An attacker can force authentication cookies — including session tokens and auto-login tokens — to be scoped to an attacker-controlled domain, facilitating session hijacking...