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OpenAdvisories
Medium · 4.3 CVE-2026-42276 EUVD-2026-28524

Onyx: IDOR in /chat/stop-chat-session allows any authenticated user to interrupt other users chat sessions

Published May 8, 2026 · Updated May 8, 2026 · Assigned by GitHub_M

Description

Onyx is an open-source AI platform. Prior to versions 3.0.9, 3.1.6, and 3.2.6, the POST /chat/stop-chat-session/{chat_session_id} endpoint lets any authenticated user stop any other user's active chat session. The endpoint checks authentication but never verifies the session belongs to the caller. An attacker who knows a chat session UUID can kill another user's LLM generation mid-stream. This issue has been patched in versions 3.0.9, 3.1.6, and 3.2.6.

Affected products

VendorProductAffectedFixed
onyx-dot-app onyx < 3.0.9, >= 3.1.0, < 3.1.6, >= 3.2.0, < 3.2.6 —

References