mustafaakin cast-localvideo - Unauthenticated Path Traversal via dir Parameter

A path traversal vulnerability in mustafaakin/cast-localvideo (all versions) allows an unauthenticated remote attacker to read arbitrary files from the server. The app.js handler at lines 151-153 passes the user-supplied req.body.dir parameter directly to res.sendFile() without sanitization, enabling directory traversal via absolute paths or ../ sequences to read sensitive system files.