{"id":"CVE-2026-31943","aliases":["EUVD-2026-16764","GHSA-w5r7-4f94-vp4c"],"status":"published","title":"LibreChat has SSRF protection bypass via IPv4-mapped IPv6 normalization in isPrivateIP","description":"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.","severity":{"version":"3.1","score":8.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00221,"percentile":0.12857,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-918"],"published":"2026-03-27T19:21:50Z","modified":"2026-10-28T02:31:09Z","products":[{"vendor":"danny-avila","product":"librechat"},{"vendor":"librechat","product":"librechat"}],"references":[{"url":"https://github.com/danny-avila/LibreChat/security/advisories/GHSA-w5r7-4f94-vp4c","tags":["x_refsource_CONFIRM","exploit","Exploit","Vendor Advisory","advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31943.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31943","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-31943","title":"LibreChat has SSRF protection bypass via IPv4-mapped IPv6 normalization in isPrivateIP","description":"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.","status":"published","published":"2026-03-27T19:21:50.653Z","modified":"2026-03-31T19:10:14.342Z","cvss":[{"version":"3.1","score":8.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T14:19:51.277563Z"}],"euvd":[{"id":"EUVD-2026-16764","description":"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.","status":"published","published":"2026-03-27T19:21:50Z","modified":"2026-03-31T19:10:14Z","cvss":[{"version":"3.1","score":8.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N","level":"high"}],"updated_at":"2026-11-02T19:25:24.493801Z"}],"nvd":[{"id":"CVE-2026-31943","description":"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.","status":"published","published":"2026-03-27T20:16:29.897Z","modified":"2026-10-26T21:10:00.17Z","cvss":[{"version":"3.1","score":8.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N","level":"high","assessor":"secondary"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T14:12:11.678711Z"}],"osv":[{"id":"CVE-2026-31943","title":"LibreChat has SSRF protection bypass via IPv4-mapped IPv6 normalization in isPrivateIP","description":"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.","status":"published","published":"2026-03-27T19:21:50.653Z","modified":"2026-10-28T02:31:09.816795006Z","cvss":[{"version":"3.1","score":8.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N","level":"high"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T15:45:01.218144Z"}]}}