CVE-2026-31950

LibreChat is a ChatGPT clone with additional features. In versions 0.8.2-rc2 through 0.8.2-rc3, the SSE streaming endpoint `/api/agents/chat/stream/:streamId` does not verify that the requesting user owns the stream. Any authenticated user who obtains or guesses a valid stream ID can subscribe and read another user's real-time chat content, including messages, AI responses, and tool invocations. Version 0.8.2 patches the issue.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/danny-avila/LibreChat/security/advisories/GHSA-f6rf-vm44-wh5g	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:librechat:librechat:0.8.2:rc2::::::
	cpe:2.3:a:librechat:librechat:0.8.2:rc3::::::

History

26 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) LibreChat es un clon de ChatGPT con características adicionales. En las versiones 0.8.2-rc2 hasta 0.8.2-rc3, el endpoint de streaming SSE “/API/agents/chat/stream/:streamId” no verifica que el usuario solicitante sea el propietario del stream. Cualquier usuario autenticado que obtenga o adivine un ID de stream válido puede suscribirse y leer el contenido de chat en tiempo real de otro usuario, incluyendo mensajes, respuestas de IA e invocaciones de herramientas. La versión 0.8.2 corrige el problema.

Information

Published : 2026-03-27 20:16

Updated : 2026-10-26 21:10

NVD link : CVE-2026-31950

Mitre link : CVE-2026-31950

CVE.ORG link : CVE-2026-31950

JSON object : View

Products Affected

librechat

librechat

CWE

CWE-284

Improper Access Control

CWE-639

Authorization Bypass Through User-Controlled Key

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