CVE-2026-72816 (GCVE-0-2026-72816)

Vulnerability from cvelistv5 – Published: 2026-08-14 11:35 – Updated: 2026-08-14 15:22
VLAI
Title
go-chi chi before 5.3.0 IP Spoofing via RealIP Middleware
Summary
go-chi/chi through 5.2.1 contains an IP spoofing vulnerability in the RealIP middleware (middleware/realip.go). The realIP() function reads client-controlled headers (True-Client-IP, X-Real-IP, and X-Forwarded-For) and overwrites r.RemoteAddr without verifying that the request originated from a trusted proxy. Attackers can supply arbitrary IP addresses in these headers to bypass IP-based access controls, evade rate limiting and geo-IP restrictions, and pollute audit logs. Fixed in 5.3.0.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-14 15:21 UTC
CWE
  • CWE-290 - Authentication Bypass by Spoofing
Assigner
References
Impacted products
Vendor Product Version CPE status
go-chi chi Affected: 0 , < 5.3.0 (semver)
Unaffected: 5.3.0 (semver)
guessed Create a notification for this product.
Date Public
2026-05-22 00:00
Credits
rezmoss
Show details on NVD website
To clipboard 

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}



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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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