An XSS issue was discovered in manage_user_page.php in MantisBT 2.x before 2.5.2. The 'filter' field is not sanitized before being rendered in the Manage User page, allowing remote attackers to execute arbitrary JavaScript code if CSP is disabled.

MantisBT before 1.3.11, 2.x before 2.3.3, and 2.4.x before 2.4.1 omits a backslash check in string_api.php and consequently has conflicting interpretations of an initial \/ substring as introducing either a local pathname or a remote hostname, which leads to (1) arbitrary Permalink Injection via CSRF attacks on a permalink_page.php?url= URI and (2) an open redirect via a login_page.php?return= URI.