CVE-2026-31943 PUBLISHED

LibreChat has SSRF protection bypass via IPv4-mapped IPv6 normalization in isPrivateIP

Assigner: GitHub_M
Reserved: 10.03.2026 Published: 27.03.2026 Updated: 27.03.2026

LibreChat is a ChatGPT clone with additional features. Prior to version 0.8.3, isPrivateIP() in packages/api/src/auth/domain.ts fails to detect IPv4-mapped IPv6 addresses in their hex-normalized form, allowing any authenticated user to bypass SSRF protection and make the server issue HTTP requests to internal network resources — including cloud metadata services (e.g., AWS 169.254.169.254), loopback, and RFC1918 ranges. Version 0.8.3 fixes the issue.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N
CVSS Score: 8.5

Product Status

Vendor danny-avila
Product LibreChat
Versions
  • Version < 0.8.3 is affected

References

Problem Types

  • CWE-918: Server-Side Request Forgery (SSRF) CWE