WWBN AVideo is an open source video platform. In versions up to and including 26.0, the aVideoEncoderChunk.json.php endpoint is a completely standalone PHP script with no authentication, no framework includes, and no resource limits. An unauthenticated remote attacker can send arbitrary POST data which is written to persistent temp files in /tmp/ with no size cap, no rate limiting, and no cleanup mechanism. This allows trivial disk space exhaustion leading to denial of service of the entire server. Commit 33d1bae6c731ef1682fcdc47b428313be073a5d1 contains a patch.