CVE-2026-42276

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.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/onyx-dot-app/onyx/security/advisories/GHSA-rw6w-hp62-gc8w	Exploit Vendor Advisory
https://github.com/onyx-dot-app/onyx/security/advisories/GHSA-rw6w-hp62-gc8w	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:onyx:onyx::::::::
	cpe:2.3:a:onyx:onyx::::::::
	cpe:2.3:a:onyx:onyx::::::::

History

No history.

Information

Published : 2026-05-08 05:16

Updated : 2026-06-17 10:47

NVD link : CVE-2026-42276

Mitre link : CVE-2026-42276

CVE.ORG link : CVE-2026-42276

JSON object : View

Products Affected

onyx

onyx

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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