Onyx up to 3.0.8/3.1.5/3.2.5 Endpoint /chat/stop-chat-session/ authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.2$0-$5k0.00

Summaryinfo

A vulnerability described as problematic has been identified in Onyx up to 3.0.8/3.1.5/3.2.5. Affected by this vulnerability is an unknown functionality of the file /chat/stop-chat-session/ of the component Endpoint. The manipulation results in authorization. This vulnerability is known as CVE-2026-42276. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Onyx up to 3.0.8/3.1.5/3.2.5. Affected is an unknown code block of the file /chat/stop-chat-session/ of the component Endpoint. The manipulation with an unknown input leads to a authorization vulnerability. CWE is classifying the issue as CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. This is going to have an impact on availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability is traded as CVE-2026-42276 since 04/26/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Technical details are known, but there is no available exploit.

Upgrading to version 3.0.9, 3.1.6 or 3.2.6 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.3
CNA Vector (GitHub_M): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authorization
CWE: CWE-639 / CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Onyx 3.0.9/3.1.6/3.2.6

Timelineinfo

04/26/2026 CVE reserved
05/08/2026 +12 days Advisory disclosed
05/08/2026 +0 days VulDB entry created
05/08/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: GHSA-rw6w-hp62-gc8w
Status: Confirmed

CVE: CVE-2026-42276 (🔒)
GCVE (CVE): GCVE-0-2026-42276
GCVE (VulDB): GCVE-100-362010

Entryinfo

Created: 05/08/2026 07:33
Changes: 05/08/2026 07:33 (64)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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