Multiple cross-site scripting (XSS) vulnerabilities in SquirrelMail before 1.4.18 and NaSMail before 1.7 allow remote attackers to inject arbitrary web script or HTML via vectors involving (1) certain encrypted strings in e-mail headers, related to contrib/decrypt_headers.php; (2) PHP_SELF; and (3) the query string (aka QUERY_STRING).
CWE-79