CVE-2026-31950: LibreChat's IDOR in SSE Stream Subscription Allows Reading Other Users' Chats
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.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-31950?
CVE-2026-31950 is classified as a high severity vulnerability due to its potential for unauthorized access to sensitive user data.
How do I fix CVE-2026-31950?
To fix CVE-2026-31950, ensure that the SSE streaming endpoint properly verifies user ownership of the chat stream before allowing access.
Which versions of LibreChat are affected by CVE-2026-31950?
CVE-2026-31950 affects LibreChat versions 0.8.2-rc2 through 0.8.2-rc3.
What type of vulnerability is CVE-2026-31950?
CVE-2026-31950 is an Insecure Direct Object Reference (IDOR) vulnerability that allows unauthorized access to other users' chats.
What impact does CVE-2026-31950 have on users?
CVE-2026-31950 can lead to unauthorized users reading private chat messages from other users, compromising user privacy.