CVE-2026-31943
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.
- Affected products
- Librechat
- Librechat
- < 0.8.3
- Fix
- Available
- CVSS 3.1
- 8.5 HIGH
- EPSS
- 0.2% (12th percentile)
- Weakness
- CWE-918
- NVD status
- Modified
- Published
- 2026-03-27
CVE-2026-31943 at NVD
No indexed exploits for CVE-2026-31943 yet
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No exploit for CVE-2026-31943 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.