CVE-2026-72817

go-chi/chi versions 0.9.0 before 5.3.0 contains an IP spoofing vulnerability in the RealIP middleware, which resolves the request source IP (Request.RemoteAddr) using the first IP in the X-Forwarded-For header without validating trusted proxies. A malicious client can prepend a forged IP as the first value of the X-Forwarded-For header to spoof the request source IP, potentially bypassing access controls or falsifying request logs.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/go-chi/chi/security/advisories/GHSA-9g5q-2w5x-hmxf
https://www.vulncheck.com/advisories/go-chi-chi-before-ip-spoofing-via-x-forwarded-for

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-14 12:16

Updated : 2026-09-09 20:35

NVD link : CVE-2026-72817

Mitre link : CVE-2026-72817

CVE.ORG link : CVE-2026-72817

JSON object : View

Products Affected

No product.

CWE

CWE-345

Insufficient Verification of Data Authenticity

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