Librechat · Librechat · CVE-2026-31943
**Name of the Vulnerable Software and Affected Versions**
LibreChat versions prior to 0.8.3
**Description**
LibreChat is a ChatGPT clone with additional features. Prior to version 0.8.3, the `isPrivateIP()` function in `packages/api/src/auth/domain.ts` does not correctly identify IPv4-mapped IPv6 addresses in their hex-normalized form. This allows any authenticated user to bypass Server-Side Request Forgery (SSRF) protection. Successful exploitation enables the server to make HTTP requests to internal network resources, including cloud metadata services (e.g., AWS `169.254.169.254`), loopback, and RFC1918 ranges. The vulnerable function is `isPrivateIP()`. The affected API endpoint is not explicitly mentioned.
**Recommendations**
Upgrade to version 0.8.3 to resolve this issue.