GHSA-v64v-r7qm-w5x4: WWBN AVideo Path Traversal Arbitrary VTT File Write via receiveAsync.json.php

WWBN AVideo contains a path traversal vulnerability in plugin/AI/receiveAsync.json.php that allows holders of any valid AI token to write arbitrary .vtt files by injecting traversal sequences into the unsanitized response[lang] parameter. Attackers can send a type=translation request with a crafted lang value to plant attacker-controlled content in the webroot or overwrite other users' subtitle files.