Missing Authentication for Critical Function

Summary

AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 contain an unauthenticated file read vulnerability via the download.php script. The endpoint exposes a file download mechanism that lacks access control, allowing remote, unauthenticated users to request files stored on the appliance based solely on attacker-supplied path and filename parameters. While limited to specific file extensions permitted by the application logic, sensitive backup archives can be retrieved, exposing internal databases and credential hashes. Successful exploitation may lead to disclosure of administrative password hashes and other sensitive configuration data.