CVE
CVE-2026-31943
LibreChat has SSRF protection bypass via IPv4-mapped IPv6 normalization in isPrivateIP
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.
Package Versions Affected
Package Version
patch Availability
No items found.
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CVSS Version
Severity
Base Score
CVSS Version
Score Vector
C
H
U
8.5
-
3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N
C
H
U
0
-
3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N
C
H
U
-
Related Resources
No items found.
References
https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31943.json, https://github.com/danny-avila/LibreChat/security/advisories/GHSA-w5r7-4f94-vp4c, https://nvd.nist.gov/vuln/detail/CVE-2026-31943
Basic Information
Ecosystem
