CVE-2026-72817

go-chi chi 0.9.0 before 5.3.0 IP Spoofing via X-Forwarded-For

MEDIUM
6.5
CVSS Score
Published: August 14, 2026 at 11:35 AM UTC
Updated: October 8, 2026 at 04:17 PM UTC
1 product affected across 1 vendorChi

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Severity
MEDIUM6.5
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

0.9.0 ≤ v < 5.3.00.9.0
Vendor states this is fixed in 5.3.0 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.5MEDIUMVulnCheck
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-345

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