CVE-2026-114437

Chi Client IP Spoofing in ClientIPFromXFF via X-Forwarded-For

Published Oct 21, 2026 CVSS 4.0 · 6.3 Medium EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-j6qf-3m9c-vwj3 chi: Client IP spoofing in ClientIPFromXFF via X-Forwarded-For
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Go-chi
Go-chi chi
Vendors & Products Go-chi
Go-chi chi
Type Values Removed Values Added
Description 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.
Title Chi Client IP Spoofing in ClientIPFromXFF via X-Forwarded-For
Weaknesses CWE-348
References
Metrics cvssV3_1

{'score': 4.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N'}

cvssV4_0

{'score': 6.3, 'vector': '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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
tenable
Published
Updated
Oct 21, 2026, 5:19 PM
Reserved
Oct 21, 2026, 1:42 PM
Status
Deferred
Published
Oct 21, 2026, 2:17 PM
Modified
Oct 21, 2026, 6:17 PM
Severity
Moderate
Public date
Oct 21, 2026, 1:52 PM