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CVE-2026-42276

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

Published: May 8, 2026Updated: May 12, 2026 Sources: CVE List NVDCWE-639
4.3MEDIUM
NVD MITRE
EPSS Score
0.3%
Top 80.2%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Not available

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:LUI:NS:UC:NI:NA:L
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:LAvailability
Low
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Weaknesses

CWE-639

Affected Products

onyx-dot-app
aka onyx
onyxOn-prem
Web & CMS Plugins / site-builder
onyx
commercial
onyxOn-prem
Consumer Software / file-utility

Exploitability

Official Patch Available

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Initial Access
View detailed technique mapping

References

https://github.com/onyx-dot-app/onyx/security/advisories/GHSA-rw6w-hp62-gc8w
github.com

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