FKIE_CVE-2026-78662

Vulnerability from fkie_nvd - Published: 2026-09-02 20:17 - Updated: 2026-09-04 16:33
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Summary
Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection. Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.
References
security@golang.orghttps://go.dev/cl/826504Patch
security@golang.orghttps://go.dev/issue/81316Issue Tracking, Vendor Advisory
security@golang.orghttps://groups.google.com/g/golang-announce/c/1y3fb2np35UMailing List, Vendor Advisory
security@golang.orghttps://pkg.go.dev/vuln/GO-2026-6354Patch, Vendor Advisory
Impacted products
Vendor Product Version
golang crypto *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "packageName": "golang.org/x/crypto/ssh",
          "product": "golang.org/x/crypto/ssh",
          "programRoutines": [
            {
              "name": "channel.handlePacket"
            },
            {
              "name": "channel.responseMessageReceived"
            },
            {
              "name": "channel.Accept"
            },
            {
              "name": "Dial"
            },
            {
              "name": "NewClientConn"
            },
            {
              "name": "NewControlClientConn"
            },
            {
              "name": "NewServerConn"
            }
          ],
          "vendor": "golang.org/x/crypto",
          "versions": [
            {
              "lessThan": "0.56.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "security@golang.org"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:golang:crypto:*:*:*:*:*:go:*:*",
              "matchCriteriaId": "77BD237B-17A1-4B39-A1E7-CBE22C5295F0",
              "versionEndExcluding": "0.56.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Previously, a channel registered in the mux\u0027s chanList is not usable until it is established. A malicious peer was able flood the channel\u0027s incomingRequests, deadlocking the entire connection. Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection."
    }
  ],
  "id": "CVE-2026-78662",
  "lastModified": "2026-09-04T16:33:34.057",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-78662",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-03T13:19:47.340520Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-02T20:17:37.167",
  "references": [
    {
      "source": "security@golang.org",
      "tags": [
        "Patch"
      ],
      "url": "https://go.dev/cl/826504"
    },
    {
      "source": "security@golang.org",
      "tags": [
        "Issue Tracking",
        "Vendor Advisory"
      ],
      "url": "https://go.dev/issue/81316"
    },
    {
      "source": "security@golang.org",
      "tags": [
        "Mailing List",
        "Vendor Advisory"
      ],
      "url": "https://groups.google.com/g/golang-announce/c/1y3fb2np35U"
    },
    {
      "source": "security@golang.org",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "url": "https://pkg.go.dev/vuln/GO-2026-6354"
    }
  ],
  "sourceIdentifier": "security@golang.org",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-770"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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