vllm-project vllm version 0.5.2.2 is vulnerable to Denial of Service attacks. The issue occurs in the 'POST /v1/completions' and 'POST /v1/embeddings' endpoints. For 'POST /v1/completions', enabling 'use_beam_search' and setting 'best_of' to a high value causes the HTTP connection to time out, with vllm ceasing effective work and the request remaining in a 'pending' state, blocking new completion requests. For 'POST /v1/embeddings', supplying invalid inputs to the JSON object causes an issue in the background loop, resulting in all further completion requests returning a 500 HTTP error code ('Internal Server Error') until vllm is restarted.

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CWE-400

https://huntr.com/bounties/8ce20bbe-3c96-4cd1-97e5-25a5630925be