{"id":"DEBIAN-CVE-2026-72816","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.","modified":"2026-09-29T13:04:22.211240613Z","published":"2026-08-14T12:16:44.620Z","upstream":["CVE-2026-72816"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-72816"}],"affected":[{"package":{"name":"golang-github-go-chi-chi","ecosystem":"Debian:12","purl":"pkg:deb/debian/golang-github-go-chi-chi?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.0.7-1","5.1.0-1","5.2.0-1","5.2.3-1","5.2.5-1","5.3.0-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-72816.json"}},{"package":{"name":"golang-github-go-chi-chi","ecosystem":"Debian:13","purl":"pkg:deb/debian/golang-github-go-chi-chi?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.2.0-1","5.2.3-1","5.2.5-1","5.3.0-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-72816.json"}},{"package":{"name":"golang-github-go-chi-chi","ecosystem":"Debian:14","purl":"pkg:deb/debian/golang-github-go-chi-chi?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.3.0-1"}]}],"versions":["5.2.0-1","5.2.3-1","5.2.5-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"}]}