{"id":"CVE-2026-72816","summary":"go-chi chi before 5.3.0 IP Spoofing via RealIP Middleware","details":"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.","aliases":["GHSA-rjr7-jggh-pgcp","GO-2026-5777"],"modified":"2026-08-16T03:48:33.629072698Z","published":"2026-08-14T11:35:28.145Z","database_specific":{"cna_assigner":"VulnCheck","cwe_ids":["CWE-290"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72816.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72816.json"},{"type":"ADVISORY","url":"https://github.com/go-chi/chi/security/advisories/GHSA-rjr7-jggh-pgcp"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-72816"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/go-chi-chi-before-ip-spoofing-via-realip-middleware"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/go-chi/chi","events":[{"introduced":"0"},{"fixed":"3b171578ca44dfd75ca3c5cbddc7b44c600a7b49"}],"database_specific":{"source":["AFFECTED_FIELD","DESCRIPTION"],"extracted_events":[{"introduced":"0"},{"fixed":"5.3.0"},{"fixed":"5.2.1"}]}}],"versions":["v5.2.5","v5.2.4","v5.2.3","v5.2.2","v5.2.1","v5.2.0","v5.1.0","v5.0.14","v5.0.13","v5.0.12","v5.0.11","v4.1.2","v3.3.4","v2.1.0","v1.5.4","v5.0.10","v5.0.9","v5.0.8","v5.0.7","v5.0.6","v5.0.5","v5.0.4","v5.0.3","v5.0.2","v5.0.1","v5.0.0","v1.5.3","v1.5.2","v1.5.1","v4.1.1","v4.1.0","v4.0.4","v4.0.3","v4.0.2","v4.0.1","v4.0.0","v3.3.3","v3.3.2","v3.3.1","v3.3.0","v3.2.1","v3.2.0","v3.1.5","v3.1.4","v3.1.3","v3.1.2","v3.1.1","v3.1.0","v3.0.0","v2.0.0","v1.0.0","v0.9.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72816.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"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"}]}