Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Multiple directory traversal vulnerabilities in Private Messaging System (PMS) 1.2.3 and earlier for PunBB allow remote attackers to include and execute arbitrary files via a .. (dot dot) in the pun_user[language] parameter to (1) functions_navlinks.php, (2) header_new_messages.php, (3) profile_send.php, and (4) viewtopic_PM-link.php in include/pms/.
CWE-22 - Path Traversal
Path traversal (or directory traversal), is a vulnerability that allows malicious users to traverse the server's root directory, gaining access to arbitrary files and folders such as application code & data, back-end credentials, and sensitive operating system files. In the worst-case scenario, an attacker could potentially execute arbitrary files on the server, resulting in a denial of service attack. Such an exploit may severely impact the integrity, confidentiality, and availability of an application.