SB2026042789 - Improper access control in LibreChat
Published: April 27, 2026
Security Bulletin ID
SB2026042789
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Information disclosure
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Improper access control (CVE-ID: CVE-2026-31950)
CWE-ID: CWE-284 - Improper Access Control
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a remote user to disclose sensitive information.
The vulnerability exists due to improper access control in the /api/agents/chat/stream/:streamId endpoint when handling SSE stream subscription requests. A remote user can send a request with a valid stream ID to disclose sensitive information.
Only instances with agents enabled are vulnerable.
Remediation
Install update from vendor's website.