CVE-2026-114437CWE-348

CVE-2026-114437

Medium · published October 21, 2026

CVSS v3.1
4.8
EPSS
0%
Percentile
2.1
In the wild
Unconfirmed
What it is

In the Golang Chi web framework, the ClientIPFromXFF middleware skips any X-Forwarded-For entry in a configured trusted CIDR but never verifies that the direct TCP peer in http.Request.RemoteAddr belongs to that CIDR. A client that can reach the Go server directly can therefore append a trusted-looking proxy address and choose the client IP returned by middleware.GetClientIP.

This issue affects chi before 5.4.0.

The record
Technical detail
CVSS v3.1
4.8 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
CVSS v4.0
6.3 · CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
EPSS
0.00126 · 2.1th percentile
Weakness
CWE-348 · Use of Less Trusted Source
Published
2026-10-21T18:17Z
References (2)
https://github.com/go-chi/chi/security/advisories/GHSA-j6qf-3m9c-vwj3 · [email protected]https://www.tenable.com/security/research/tra-2026-66 · [email protected]
EPSS history
Timeline
  • 23 OCT 03:55Z
    EPSS moved — → 0%
    epss
  • 21 OCT 13:52Z
    Chi Client IP Spoofing in ClientIPFromXFF via X-Forwarded-For
    cvelistv5
  • 21 OCT 13:52Z
    Chi Client IP Spoofing in ClientIPFromXFF via X-Forwarded-For
    cvelistv5