{"id":"GO-2021-0241","summary":"Attacker can drop certain headers in net/http/httputil","details":"ReverseProxy can be made to forward certain hop-by-hop headers, including Connection. If the target of the ReverseProxy is itself a reverse proxy, this lets an attacker drop arbitrary headers, including those set by the ReverseProxy.Director.","aliases":["BIT-golang-2021-33197","CVE-2021-33197"],"modified":"2026-03-17T04:06:01.434304Z","published":"2022-02-17T17:33:16Z","database_specific":{"url":"https://pkg.go.dev/vuln/GO-2021-0241","review_status":"REVIEWED"},"references":[{"type":"FIX","url":"https://go.dev/cl/321929"},{"type":"FIX","url":"https://go.googlesource.com/go/+/950fa11c4cb01a145bb07eeb167d90a1846061b3"},{"type":"WEB","url":"https://groups.google.com/g/golang-announce/c/RgCMkAEQjSI"},{"type":"REPORT","url":"https://go.dev/issue/46313"}],"affected":[{"package":{"name":"stdlib","ecosystem":"Go","purl":"pkg:golang/stdlib"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.15.13"},{"introduced":"1.16.0-0"},{"fixed":"1.16.5"}]}],"ecosystem_specific":{"imports":[{"symbols":["ReverseProxy.ServeHTTP"],"path":"net/http/httputil"}]},"database_specific":{"source":"https://vuln.go.dev/ID/GO-2021-0241.json"}}],"schema_version":"1.7.5","credits":[{"name":"Mattias Grenfeldt (https://grenfeldt.dev)"},{"name":"Asta Olofsson"}]}