{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-97054", "assignerOrgId": "1bb62c36-49e3-4200-9d77-64a1400537cc", "state": "PUBLISHED", "assignerShortName": "Go", "dateReserved": "2026-09-23T23:05:04.988Z", "datePublished": "2026-11-11T03:13:17.877Z", "dateUpdated": "2026-11-11T03:13:17.877Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc", "shortName": "Go", "dateUpdated": "2026-11-11T03:13:17.877Z"}, "title": "HTTP/1 server crash due to MaxBytesReader header race in net/http", "descriptions": [{"lang": "en", "value": "For HTTP/1 servers, when MaxBytesReader's limit is exceeded, \"Connection: close\" header is automatically set without synchronization, which might race with another header being set explicitly in the server handler. As a result, an HTTP/1 server that utilizes MaxBytesReader or MaxBytesHandler can crash due to runtime panic if its handler reads the request body concurrently with writing the response header."}], "affected": [{"vendor": "Go standard library", "product": "net/http", "collectionURL": "https://pkg.go.dev", "packageName": "net/http", "versions": [{"version": "0", "lessThan": "1.26.11", "status": "affected", "versionType": "semver"}, {"version": "1.27.0-0", "lessThan": "1.27.4", "status": "affected", "versionType": "semver"}], "programRoutines": [{"name": "maxBytesReader.Read"}, {"name": "CanonicalHeaderKey"}, {"name": "Client.CloseIdleConnections"}, {"name": "Client.Do"}, {"name": "Client.Get"}, {"name": "Client.Head"}, {"name": "Client.Post"}, {"name": "Client.PostForm"}, {"name": "ClientConn.Close"}, {"name": "ClientConn.RoundTrip"}, {"name": "Cookie.String"}, {"name": "Cookie.Valid"}, {"name": "CrossOriginProtection.AddInsecureBypassPattern"}, {"name": "CrossOriginProtection.AddTrustedOrigin"}, {"name": "CrossOriginProtection.Check"}, {"name": "Dir.Open"}, {"name": "Error"}, {"name": "Get"}, {"name": "Handle"}, {"name": "HandleFunc"}, {"name": "HandlerFunc.ServeHTTP"}, {"name": "Head"}, {"name": "Header.Add"}, {"name": "Header.Del"}, {"name": "Header.Get"}, {"name": "Header.Set"}, {"name": "Header.Values"}, {"name": "Header.Write"}, {"name": "Header.WriteSubset"}, {"name": "ListenAndServe"}, {"name": "ListenAndServeTLS"}, {"name": "NewRequest"}, {"name": "NewRequestWithContext"}, {"name": "NotFound"}, {"name": "ParseCookie"}, {"name": "ParseSetCookie"}, {"name": "ParseTime"}, {"name": "Post"}, {"name": "PostForm"}, {"name": "ProxyFromEnvironment"}, {"name": "ReadRequest"}, {"name": "ReadResponse"}, {"name": "Redirect"}, {"name": "Request.AddCookie"}, {"name": "Request.BasicAuth"}, {"name": "Request.Cookie"}, {"name": "Request.Cookies"}, {"name": "Request.CookiesNamed"}, {"name": "Request.FormFile"}, {"name": "Request.FormValue"}, {"name": "Request.MultipartReader"}, {"name": "Request.ParseForm"}, {"name": "Request.ParseMultipartForm"}, {"name": "Request.PostFormValue"}, {"name": "Request.Referer"}, {"name": "Request.SetBasicAuth"}, {"name": "Request.UserAgent"}, {"name": "Request.Write"}, {"name": "Request.WriteProxy"}, {"name": "Response.Cookies"}, {"name": "Response.Location"}, {"name": "Response.Write"}, {"name": "ResponseController.EnableFullDuplex"}, {"name": "ResponseController.Flush"}, {"name": "ResponseController.Hijack"}, {"name": "ResponseController.SetReadDeadline"}, {"name": "ResponseController.SetWriteDeadline"}, {"name": "Serve"}, {"name": "ServeContent"}, {"name": "ServeFile"}, {"name": "ServeFileFS"}, {"name": "ServeMux.Handle"}, {"name": "ServeMux.HandleFunc"}, {"name": "ServeMux.ServeHTTP"}, {"name": "ServeTLS"}, {"name": "Server.Close"}, {"name": "Server.ListenAndServe"}, {"name": "Server.ListenAndServeTLS"}, {"name": "Server.Serve"}, {"name": "Server.ServeTLS"}, {"name": "Server.SetKeepAlivesEnabled"}, {"name": "Server.Shutdown"}, {"name": "SetCookie"}, {"name": "Transport.CancelRequest"}, {"name": "Transport.Clone"}, {"name": "Transport.CloseIdleConnections"}, {"name": "Transport.NewClientConn"}, {"name": "Transport.RoundTrip"}, {"name": "body.Close"}, {"name": "body.Read"}, {"name": "bodyEOFSignal.Close"}, {"name": "bodyEOFSignal.Read"}, {"name": "bodyLocked.Read"}, {"name": "bufioFlushWriter.Write"}, {"name": "cancelTimerBody.Close"}, {"name": "cancelTimerBody.Read"}, {"name": "checkConnErrorWriter.Write"}, {"name": "chunkWriter.Write"}, {"name": "connReader.Read"}, {"name": "connectMethodKey.String"}, {"name": "expectContinueReader.Close"}, {"name": "expectContinueReader.Read"}, {"name": "extraHeader.Write"}, {"name": "fileHandler.ServeHTTP"}, {"name": "fileTransport.RoundTrip"}, {"name": "globalOptionsHandler.ServeHTTP"}, {"name": "gzipReader.Close"}, {"name": "gzipReader.Read"}, {"name": "http1ClientConn.Close"}, {"name": "http1ClientConn.RoundTrip"}, {"name": "http2ClientConn.RoundTrip"}, {"name": "http2Handler.ServeHTTP"}, {"name": "http2ResponseWriter.Flush"}, {"name": "http2ResponseWriter.FlushError"}, {"name": "http2ResponseWriter.Push"}, {"name": "http2RoundTripper.RoundTrip"}, {"name": "http3ServerHandler.ServeHTTP"}, {"name": "initALPNRequest.ServeHTTP"}, {"name": "loggingConn.Close"}, {"name": "loggingConn.Read"}, {"name": "loggingConn.Write"}, {"name": "maxBytesReader.Close"}, {"name": "onceCloseListener.Close"}, {"name": "persistConn.Read"}, {"name": "persistConnWriter.ReadFrom"}, {"name": "persistConnWriter.Write"}, {"name": "populateResponse.Write"}, {"name": "populateResponse.WriteHeader"}, {"name": "readTrackingBody.Close"}, {"name": "readTrackingBody.Read"}, {"name": "readWriteCloserBody.CloseWrite"}, {"name": "readWriteCloserBody.Read"}, {"name": "redirectHandler.ServeHTTP"}, {"name": "response.Flush"}, {"name": "response.FlushError"}, {"name": "response.Hijack"}, {"name": "response.ReadFrom"}, {"name": "response.Write"}, {"name": "response.WriteHeader"}, {"name": "response.WriteString"}, {"name": "serverHandler.ServeHTTP"}, {"name": "socksDialer.DialWithConn"}, {"name": "socksUsernamePassword.Authenticate"}, {"name": "stringWriter.WriteString"}, {"name": "timeoutHandler.ServeHTTP"}, {"name": "timeoutWriter.Write"}, {"name": "timeoutWriter.WriteHeader"}, {"name": "transportReadFromServerError.Error"}, {"name": "unencryptedHTTP2Request.ServeHTTP"}], "defaultStatus": "unaffected"}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "CWE-820: Missing Synchronization"}]}], "references": [{"url": "https://go.dev/cl/862185"}, {"url": "https://go.dev/issue/82563"}, {"url": "https://groups.google.com/g/golang-announce/c/iY8TY0wWgbM"}, {"url": "https://pkg.go.dev/vuln/GO-2026-6859"}], "credits": [{"lang": "en", "value": "Jakub Ciolek (https://ciolek.dev)"}]}}}

{}

{"affected": [{"affectedData": [{"collectionURL": "https://pkg.go.dev", "defaultStatus": "unaffected", "packageName": "net/http", "product": "net/http", "programRoutines": [{"name": "maxBytesReader.Read"}, {"name": "CanonicalHeaderKey"}, {"name": "Client.CloseIdleConnections"}, {"name": "Client.Do"}, {"name": "Client.Get"}, {"name": "Client.Head"}, {"name": "Client.Post"}, {"name": "Client.PostForm"}, {"name": "ClientConn.Close"}, {"name": "ClientConn.RoundTrip"}, {"name": "Cookie.String"}, {"name": "Cookie.Valid"}, {"name": "CrossOriginProtection.AddInsecureBypassPattern"}, {"name": "CrossOriginProtection.AddTrustedOrigin"}, {"name": "CrossOriginProtection.Check"}, {"name": "Dir.Open"}, {"name": "Error"}, {"name": "Get"}, {"name": "Handle"}, {"name": "HandleFunc"}, {"name": "HandlerFunc.ServeHTTP"}, {"name": "Head"}, {"name": "Header.Add"}, {"name": "Header.Del"}, {"name": "Header.Get"}, {"name": "Header.Set"}, {"name": "Header.Values"}, {"name": "Header.Write"}, {"name": "Header.WriteSubset"}, {"name": "ListenAndServe"}, {"name": "ListenAndServeTLS"}, {"name": "NewRequest"}, {"name": "NewRequestWithContext"}, {"name": "NotFound"}, {"name": "ParseCookie"}, {"name": "ParseSetCookie"}, {"name": "ParseTime"}, {"name": "Post"}, {"name": "PostForm"}, {"name": "ProxyFromEnvironment"}, {"name": "ReadRequest"}, {"name": "ReadResponse"}, {"name": "Redirect"}, {"name": "Request.AddCookie"}, {"name": "Request.BasicAuth"}, {"name": "Request.Cookie"}, {"name": "Request.Cookies"}, {"name": "Request.CookiesNamed"}, {"name": "Request.FormFile"}, {"name": "Request.FormValue"}, {"name": "Request.MultipartReader"}, {"name": "Request.ParseForm"}, {"name": "Request.ParseMultipartForm"}, {"name": "Request.PostFormValue"}, {"name": "Request.Referer"}, {"name": "Request.SetBasicAuth"}, {"name": "Request.UserAgent"}, {"name": "Request.Write"}, {"name": "Request.WriteProxy"}, {"name": "Response.Cookies"}, {"name": "Response.Location"}, {"name": "Response.Write"}, {"name": "ResponseController.EnableFullDuplex"}, {"name": "ResponseController.Flush"}, {"name": "ResponseController.Hijack"}, {"name": "ResponseController.SetReadDeadline"}, {"name": "ResponseController.SetWriteDeadline"}, {"name": "Serve"}, {"name": "ServeContent"}, {"name": "ServeFile"}, {"name": "ServeFileFS"}, {"name": "ServeMux.Handle"}, {"name": "ServeMux.HandleFunc"}, {"name": "ServeMux.ServeHTTP"}, {"name": "ServeTLS"}, {"name": "Server.Close"}, {"name": "Server.ListenAndServe"}, {"name": "Server.ListenAndServeTLS"}, {"name": "Server.Serve"}, {"name": "Server.ServeTLS"}, {"name": "Server.SetKeepAlivesEnabled"}, {"name": "Server.Shutdown"}, {"name": "SetCookie"}, {"name": "Transport.CancelRequest"}, {"name": "Transport.Clone"}, {"name": "Transport.CloseIdleConnections"}, {"name": "Transport.NewClientConn"}, {"name": "Transport.RoundTrip"}, {"name": "body.Close"}, {"name": "body.Read"}, {"name": "bodyEOFSignal.Close"}, {"name": "bodyEOFSignal.Read"}, {"name": "bodyLocked.Read"}, {"name": "bufioFlushWriter.Write"}, {"name": "cancelTimerBody.Close"}, {"name": "cancelTimerBody.Read"}, {"name": "checkConnErrorWriter.Write"}, {"name": "chunkWriter.Write"}, {"name": "connReader.Read"}, {"name": "connectMethodKey.String"}, {"name": "expectContinueReader.Close"}, {"name": "expectContinueReader.Read"}, {"name": "extraHeader.Write"}, {"name": "fileHandler.ServeHTTP"}, {"name": "fileTransport.RoundTrip"}, {"name": "globalOptionsHandler.ServeHTTP"}, {"name": "gzipReader.Close"}, {"name": "gzipReader.Read"}, {"name": "http1ClientConn.Close"}, {"name": "http1ClientConn.RoundTrip"}, {"name": "http2ClientConn.RoundTrip"}, {"name": "http2Handler.ServeHTTP"}, {"name": "http2ResponseWriter.Flush"}, {"name": "http2ResponseWriter.FlushError"}, {"name": "http2ResponseWriter.Push"}, {"name": "http2RoundTripper.RoundTrip"}, {"name": "http3ServerHandler.ServeHTTP"}, {"name": "initALPNRequest.ServeHTTP"}, {"name": "loggingConn.Close"}, {"name": "loggingConn.Read"}, {"name": "loggingConn.Write"}, {"name": "maxBytesReader.Close"}, {"name": "onceCloseListener.Close"}, {"name": "persistConn.Read"}, {"name": "persistConnWriter.ReadFrom"}, {"name": "persistConnWriter.Write"}, {"name": "populateResponse.Write"}, {"name": "populateResponse.WriteHeader"}, {"name": "readTrackingBody.Close"}, {"name": "readTrackingBody.Read"}, {"name": "readWriteCloserBody.CloseWrite"}, {"name": "readWriteCloserBody.Read"}, {"name": "redirectHandler.ServeHTTP"}, {"name": "response.Flush"}, {"name": "response.FlushError"}, {"name": "response.Hijack"}, {"name": "response.ReadFrom"}, {"name": "response.Write"}, {"name": "response.WriteHeader"}, {"name": "response.WriteString"}, {"name": "serverHandler.ServeHTTP"}, {"name": "socksDialer.DialWithConn"}, {"name": "socksUsernamePassword.Authenticate"}, {"name": "stringWriter.WriteString"}, {"name": "timeoutHandler.ServeHTTP"}, {"name": "timeoutWriter.Write"}, {"name": "timeoutWriter.WriteHeader"}, {"name": "transportReadFromServerError.Error"}, {"name": "unencryptedHTTP2Request.ServeHTTP"}], "vendor": "Go standard library", "versions": [{"lessThan": "1.26.11", "status": "affected", "version": "0", "versionType": "semver"}, {"lessThan": "1.27.4", "status": "affected", "version": "1.27.0-0", "versionType": "semver"}]}], "source": "security@golang.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "For HTTP/1 servers, when MaxBytesReader's limit is exceeded, \"Connection: close\" header is automatically set without synchronization, which might race with another header being set explicitly in the server handler. As a result, an HTTP/1 server that utilizes MaxBytesReader or MaxBytesHandler can crash due to runtime panic if its handler reads the request body concurrently with writing the response header."}], "id": "CVE-2026-97054", "lastModified": "2026-11-11T05:19:58.943", "metrics": {}, "published": "2026-11-11T05:19:58.943", "references": [{"source": "security@golang.org", "url": "https://go.dev/cl/862185"}, {"source": "security@golang.org", "url": "https://go.dev/issue/82563"}, {"source": "security@golang.org", "url": "https://groups.google.com/g/golang-announce/c/iY8TY0wWgbM"}, {"source": "security@golang.org", "url": "https://pkg.go.dev/vuln/GO-2026-6859"}], "sourceIdentifier": "security@golang.org", "vulnStatus": "Received"}

{}

{}