CVE-2026-42276 (GCVE-0-2026-42276)

Vulnerability from cvelistv5 – Published: 2026-05-08 03:49 – Updated: 2026-05-08 12:57
VLAI
Title
Onyx: IDOR in /chat/stop-chat-session allows any authenticated user to interrupt other users chat sessions
Summary
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.
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-08 12:56 UTC
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
References
Impacted products
Vendor Product Version CPE status
onyx-dot-app onyx Affected: < 3.0.9
Affected: >= 3.1.0, < 3.1.6
Affected: >= 3.2.0, < 3.2.6
guessed Create a notification for this product.
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