Vulnerability-Lookup

Vulnerability from bitnami_vulndb

Published

2026-10-16 08:40

Modified

2026-10-16 09:07

Summary

Double flow control refund on HTTP/2 server streams in net/http

Details

The HTTP/2 server can refund connection-level flow control twice for the same data: Once when a client resets a stream (refunding data for any sent-but-unread portion of the stream), and again when a request handler reads the buffered data. A malicious client can exploit this to bypass the configured connection-level flow control limit (MaxReceiveBufferPerConnection). Total buffered data is still limited by the concurrent stream limit and stream-level flow control.

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "golang",
        "purl": "pkg:bitnami/golang"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.26.9"
            },
            {
              "introduced": "1.27.0-0"
            },
            {
              "fixed": "1.27.2"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H",
          "type": "CVSS_V3"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-78663"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*"
    ],
    "severity": "Critical"
  },
  "details": "The HTTP/2 server can refund connection-level flow control twice for the same data: Once when a client resets a stream (refunding data for any sent-but-unread portion of the stream), and again when a request handler reads the buffered data. A malicious client can exploit this to bypass the configured connection-level flow control limit (MaxReceiveBufferPerConnection). Total buffered data is still limited by the concurrent stream limit and stream-level flow control.",
  "id": "BIT-golang-2026-78663",
  "modified": "2026-10-16T09:07:50.945Z",
  "published": "2026-10-16T08:40:03.193Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://go.dev/cl/847187"
    },
    {
      "type": "WEB",
      "url": "https://go.dev/cl/847310"
    },
    {
      "type": "WEB",
      "url": "https://go.dev/issue/81743"
    },
    {
      "type": "WEB",
      "url": "https://groups.google.com/g/golang-announce/c/U2fTuyDJznI"
    },
    {
      "type": "WEB",
      "url": "https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-78663"
    },
    {
      "type": "WEB",
      "url": "https://pkg.go.dev/vuln/GO-2026-6612"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "Double flow control refund on HTTP/2 server streams in net/http"
}

CVE-2026-78663 (GCVE-0-2026-78663)

Vulnerability from cvelistv5 – Published: 2026-10-08 22:53 – Updated: 2026-10-09 16:42

Title

Double flow control refund on HTTP/2 server streams in net/http

Summary

Severity

9.1 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-09 16:40 UTC

CWE

CWE-675 - Multiple Operations on Resource in Single-Operation Context

Assigner

Go Google root Scorecard

References

6 references

URL	Tags
https://go.dev/cl/847187
https://go.dev/cl/847310
https://go.dev/issue/81743
https://groups.google.com/g/golang-announce/c/U2f…
https://groups.google.com/g/golang-announce/c/ZPw…
https://pkg.go.dev/vuln/GO-2026-6612

Impacted products

3 products

Vendor	Product	Version
Go standard library	net/http	Affected: 0 , < 1.26.9 (semver)
Go standard library	net/http/internal/http2	Affected: 1.27.0-0 , < 1.27.2 (semver)
golang.org/x/net	golang.org/x/net/http2	Affected: 0 , < 0.60.0 (semver)

Credits

Ali Sherif (https://www.linkedin.com/in/ali-sherif-13812b276/)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "HIGH",
              "baseScore": 9.1,
              "baseSeverity": "CRITICAL",
              "confidentialityImpact": "NONE",
              "integrityImpact": "HIGH",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-78663",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-10-09T16:40:08.220862Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-675",
                "description": "CWE-675 Multiple Operations on Resource in Single-Operation Context",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-10-09T16:42:50.839Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "packageName": "net/http",
          "product": "net/http",
          "programRoutines": [
            {
              "name": "http2requestBody.Close"
            },
            {
              "name": "http2requestBody.Read"
            },
            {
              "name": "http2serverConn.closeStream"
            },
            {
              "name": "http2serverConn.handlerDone"
            },
            {
              "name": "http2serverConn.newWriterAndRequest"
            },
            {
              "name": "http2serverConn.newWriterAndRequestNoBody"
            },
            {
              "name": "http2serverConn.noteBodyRead"
            },
            {
              "name": "http2serverConn.processHeaders"
            },
            {
              "name": "http2serverConn.runHandler"
            },
            {
              "name": "http2serverConn.scheduleHandler"
            },
            {
              "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.Close"
            },
            {
              "name": "http2ClientConn.Ping"
            },
            {
              "name": "http2ClientConn.RoundTrip"
            },
            {
              "name": "http2ClientConn.Shutdown"
            },
            {
              "name": "http2ConnectionError.Error"
            },
            {
              "name": "http2ErrCode.String"
            },
            {
              "name": "http2FrameHeader.String"
            },
            {
              "name": "http2FrameType.String"
            },
            {
              "name": "http2FrameWriteRequest.String"
            },
            {
              "name": "http2Framer.ReadFrame"
            },
            {
              "name": "http2Framer.ReadFrameForHeader"
            },
            {
              "name": "http2Framer.ReadFrameHeader"
            },
            {
              "name": "http2Framer.WriteContinuation"
            },
            {
              "name": "http2Framer.WriteData"
            },
            {
              "name": "http2Framer.WriteDataPadded"
            },
            {
              "name": "http2Framer.WriteGoAway"
            },
            {
              "name": "http2Framer.WriteHeaders"
            },
            {
              "name": "http2Framer.WritePing"
            },
            {
              "name": "http2Framer.WritePriority"
            },
            {
              "name": "http2Framer.WritePushPromise"
            },
            {
              "name": "http2Framer.WriteRSTStream"
            },
            {
              "name": "http2Framer.WriteRawFrame"
            },
            {
              "name": "http2Framer.WriteSettings"
            },
            {
              "name": "http2Framer.WriteSettingsAck"
            },
            {
              "name": "http2Framer.WriteWindowUpdate"
            },
            {
              "name": "http2GoAwayError.Error"
            },
            {
              "name": "http2Server.ServeConn"
            },
            {
              "name": "http2Setting.String"
            },
            {
              "name": "http2SettingID.String"
            },
            {
              "name": "http2SettingsFrame.ForeachSetting"
            },
            {
              "name": "http2StreamError.Error"
            },
            {
              "name": "http2Transport.CloseIdleConnections"
            },
            {
              "name": "http2Transport.NewClientConn"
            },
            {
              "name": "http2Transport.RoundTrip"
            },
            {
              "name": "http2Transport.RoundTripOpt"
            },
            {
              "name": "http2bufferedWriter.Flush"
            },
            {
              "name": "http2bufferedWriter.Write"
            },
            {
              "name": "http2bufferedWriterTimeoutWriter.Write"
            },
            {
              "name": "http2chunkWriter.Write"
            },
            {
              "name": "http2clientConnPool.GetClientConn"
            },
            {
              "name": "http2connError.Error"
            },
            {
              "name": "http2dataBuffer.Read"
            },
            {
              "name": "http2duplicatePseudoHeaderError.Error"
            },
            {
              "name": "http2gzipReader.Close"
            },
            {
              "name": "http2gzipReader.Read"
            },
            {
              "name": "http2headerFieldNameError.Error"
            },
            {
              "name": "http2headerFieldValueError.Error"
            },
            {
              "name": "http2netHTTPClientConn.Close"
            },
            {
              "name": "http2netHTTPClientConn.RoundTrip"
            },
            {
              "name": "http2noDialClientConnPool.GetClientConn"
            },
            {
              "name": "http2noDialH2RoundTripper.NewClientConn"
            },
            {
              "name": "http2noDialH2RoundTripper.RoundTrip"
            },
            {
              "name": "http2pipe.Read"
            },
            {
              "name": "http2priorityWriteSchedulerRFC7540.CloseStream"
            },
            {
              "name": "http2priorityWriteSchedulerRFC7540.OpenStream"
            },
            {
              "name": "http2priorityWriteSchedulerRFC9218.OpenStream"
            },
            {
              "name": "http2pseudoHeaderError.Error"
            },
            {
              "name": "http2responseWriter.Flush"
            },
            {
              "name": "http2responseWriter.FlushError"
            },
            {
              "name": "http2responseWriter.Push"
            },
            {
              "name": "http2responseWriter.SetReadDeadline"
            },
            {
              "name": "http2responseWriter.SetWriteDeadline"
            },
            {
              "name": "http2responseWriter.Write"
            },
            {
              "name": "http2responseWriter.WriteHeader"
            },
            {
              "name": "http2responseWriter.WriteString"
            },
            {
              "name": "http2roundRobinWriteScheduler.OpenStream"
            },
            {
              "name": "http2serverConn.CloseConn"
            },
            {
              "name": "http2serverConn.Flush"
            },
            {
              "name": "http2stickyErrWriter.Write"
            },
            {
              "name": "http2transportResponseBody.Close"
            },
            {
              "name": "http2transportResponseBody.Read"
            },
            {
              "name": "http2unencryptedTransport.RoundTrip"
            },
            {
              "name": "http2writeData.String"
            },
            {
              "name": "initALPNRequest.ServeHTTP"
            },
            {
              "name": "loggingConn.Close"
            },
            {
              "name": "loggingConn.Read"
            },
            {
              "name": "loggingConn.Write"
            },
            {
              "name": "maxBytesReader.Close"
            },
            {
              "name": "maxBytesReader.Read"
            },
            {
              "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": "1.26.9",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        },
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "packageName": "net/http/internal/http2",
          "product": "net/http/internal/http2",
          "programRoutines": [
            {
              "name": "requestBody.Close"
            },
            {
              "name": "requestBody.Read"
            },
            {
              "name": "serverConn.closeStream"
            },
            {
              "name": "serverConn.handlerDone"
            },
            {
              "name": "serverConn.newWriterAndRequest"
            },
            {
              "name": "serverConn.newWriterAndRequestNoBody"
            },
            {
              "name": "serverConn.noteBodyRead"
            },
            {
              "name": "serverConn.processHeaders"
            },
            {
              "name": "serverConn.runHandler"
            },
            {
              "name": "serverConn.scheduleHandler"
            },
            {
              "name": "Server.ServeConn"
            }
          ],
          "vendor": "Go standard library",
          "versions": [
            {
              "lessThan": "1.27.2",
              "status": "affected",
              "version": "1.27.0-0",
              "versionType": "semver"
            }
          ]
        },
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "packageName": "golang.org/x/net/http2",
          "product": "golang.org/x/net/http2",
          "programRoutines": [
            {
              "name": "requestBody.Close"
            },
            {
              "name": "requestBody.Read"
            },
            {
              "name": "serverConn.closeStream"
            },
            {
              "name": "serverConn.handlerDone"
            },
            {
              "name": "serverConn.newWriterAndRequest"
            },
            {
              "name": "serverConn.newWriterAndRequestNoBody"
            },
            {
              "name": "serverConn.noteBodyRead"
            },
            {
              "name": "serverConn.processHeaders"
            },
            {
              "name": "serverConn.runHandler"
            },
            {
              "name": "serverConn.scheduleHandler"
            },
            {
              "name": "ClientConn.Close"
            },
            {
              "name": "ClientConn.Ping"
            },
            {
              "name": "ClientConn.RoundTrip"
            },
            {
              "name": "ClientConn.Shutdown"
            },
            {
              "name": "ConfigureServer"
            },
            {
              "name": "ConfigureTransport"
            },
            {
              "name": "ConfigureTransports"
            },
            {
              "name": "ConnectionError.Error"
            },
            {
              "name": "ErrCode.String"
            },
            {
              "name": "FrameHeader.String"
            },
            {
              "name": "FrameType.String"
            },
            {
              "name": "FrameWriteRequest.String"
            },
            {
              "name": "Framer.ReadFrame"
            },
            {
              "name": "Framer.ReadFrameForHeader"
            },
            {
              "name": "Framer.ReadFrameHeader"
            },
            {
              "name": "Framer.WriteContinuation"
            },
            {
              "name": "Framer.WriteData"
            },
            {
              "name": "Framer.WriteDataPadded"
            },
            {
              "name": "Framer.WriteGoAway"
            },
            {
              "name": "Framer.WriteHeaders"
            },
            {
              "name": "Framer.WritePing"
            },
            {
              "name": "Framer.WritePriority"
            },
            {
              "name": "Framer.WritePriorityUpdate"
            },
            {
              "name": "Framer.WritePushPromise"
            },
            {
              "name": "Framer.WriteRSTStream"
            },
            {
              "name": "Framer.WriteRawFrame"
            },
            {
              "name": "Framer.WriteSettings"
            },
            {
              "name": "Framer.WriteSettingsAck"
            },
            {
              "name": "Framer.WriteWindowUpdate"
            },
            {
              "name": "GoAwayError.Error"
            },
            {
              "name": "ReadFrameHeader"
            },
            {
              "name": "Server.ServeConn"
            },
            {
              "name": "Setting.String"
            },
            {
              "name": "SettingID.String"
            },
            {
              "name": "SettingsFrame.ForeachSetting"
            },
            {
              "name": "StreamError.Error"
            },
            {
              "name": "Transport.CloseIdleConnections"
            },
            {
              "name": "Transport.NewClientConn"
            },
            {
              "name": "Transport.RoundTrip"
            },
            {
              "name": "Transport.RoundTripOpt"
            },
            {
              "name": "bufferedWriter.Flush"
            },
            {
              "name": "bufferedWriter.Write"
            },
            {
              "name": "bufferedWriterTimeoutWriter.Write"
            },
            {
              "name": "chunkWriter.Write"
            },
            {
              "name": "clientConnPool.GetClientConn"
            },
            {
              "name": "connError.Error"
            },
            {
              "name": "dataBuffer.Read"
            },
            {
              "name": "duplicatePseudoHeaderError.Error"
            },
            {
              "name": "gzipReader.Close"
            },
            {
              "name": "gzipReader.Read"
            },
            {
              "name": "headerFieldNameError.Error"
            },
            {
              "name": "headerFieldValueError.Error"
            },
            {
              "name": "netHTTPClientConn.Close"
            },
            {
              "name": "netHTTPClientConn.RoundTrip"
            },
            {
              "name": "noDialClientConnPool.GetClientConn"
            },
            {
              "name": "noDialH2RoundTripper.NewClientConn"
            },
            {
              "name": "noDialH2RoundTripper.RoundTrip"
            },
            {
              "name": "pipe.Read"
            },
            {
              "name": "priorityWriteSchedulerRFC7540.CloseStream"
            },
            {
              "name": "priorityWriteSchedulerRFC7540.OpenStream"
            },
            {
              "name": "priorityWriteSchedulerRFC9218.OpenStream"
            },
            {
              "name": "pseudoHeaderError.Error"
            },
            {
              "name": "responseWriter.Flush"
            },
            {
              "name": "responseWriter.FlushError"
            },
            {
              "name": "responseWriter.Push"
            },
            {
              "name": "responseWriter.SetReadDeadline"
            },
            {
              "name": "responseWriter.SetWriteDeadline"
            },
            {
              "name": "responseWriter.Write"
            },
            {
              "name": "responseWriter.WriteHeader"
            },
            {
              "name": "responseWriter.WriteString"
            },
            {
              "name": "roundRobinWriteScheduler.OpenStream"
            },
            {
              "name": "serverConn.CloseConn"
            },
            {
              "name": "serverConn.Flush"
            },
            {
              "name": "stickyErrWriter.Write"
            },
            {
              "name": "transportResponseBody.Close"
            },
            {
              "name": "transportResponseBody.Read"
            },
            {
              "name": "unencryptedTransport.RoundTrip"
            },
            {
              "name": "writeData.String"
            }
          ],
          "vendor": "golang.org/x/net",
          "versions": [
            {
              "lessThan": "0.60.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Ali Sherif (https://www.linkedin.com/in/ali-sherif-13812b276/)"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The HTTP/2 server can refund connection-level flow control twice for the same data: Once when a client resets a stream (refunding data for any sent-but-unread portion of the stream), and again when a request handler reads the buffered data. A malicious client can exploit this to bypass the configured connection-level flow control limit (MaxReceiveBufferPerConnection). Total buffered data is still limited by the concurrent stream limit and stream-level flow control."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "CWE-675: Multiple Operations on Resource in Single-Operation Context",
              "lang": "en"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-08T22:53:59.772Z",
        "orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
        "shortName": "Go"
      },
      "references": [
        {
          "url": "https://go.dev/cl/847187"
        },
        {
          "url": "https://go.dev/cl/847310"
        },
        {
          "url": "https://go.dev/issue/81743"
        },
        {
          "url": "https://groups.google.com/g/golang-announce/c/U2fTuyDJznI"
        },
        {
          "url": "https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs"
        },
        {
          "url": "https://pkg.go.dev/vuln/GO-2026-6612"
        }
      ],
      "title": "Double flow control refund on HTTP/2 server streams in net/http"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
    "assignerShortName": "Go",
    "cveId": "CVE-2026-78663",
    "datePublished": "2026-10-08T22:53:59.772Z",
    "dateReserved": "2026-08-24T23:36:15.738Z",
    "dateUpdated": "2026-10-09T16:42:50.839Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

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Confirmed: The vulnerability has been validated from an analyst's perspective.
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Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

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Vulnerability from bitnami_vulndb

CVE-2026-78663 (GCVE-0-2026-78663)

Tags

Sightings

Nomenclature

Related by attack behaviour