data/cve/v5/GO-2026-6355.json

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.0",
  "cveMetadata": {
    "cveId": "CVE-2026-56855"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc"
      },
      "title": "Prevent DoS on deadlocked established channel in golang.org/x/crypto/ssh",
      "descriptions": [
        {
          "lang": "en",
          "value": "Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection. Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking."
        }
      ],
      "affected": [
        {
          "vendor": "golang.org/x/crypto",
          "product": "golang.org/x/crypto/ssh",
          "collectionURL": "https://pkg.go.dev",
          "packageName": "golang.org/x/crypto/ssh",
          "versions": [
            {
              "version": "0",
              "lessThan": "0.56.0",
              "status": "affected",
              "versionType": "semver"
            }
          ],
          "programRoutines": [
            {
              "name": "channel.handlePacket"
            },
            {
              "name": "Dial"
            },
            {
              "name": "NewClientConn"
            },
            {
              "name": "NewControlClientConn"
            },
            {
              "name": "NewServerConn"
            }
          ],
          "defaultStatus": "unaffected"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "CWE-770: Allocation of Resources Without Limits or Throttling"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://go.dev/issue/81317"
        },
        {
          "url": "https://go.dev/cl/826524"
        },
        {
          "url": "https://groups.google.com/g/golang-announce/c/1y3fb2np35U"
        },
        {
          "url": "https://pkg.go.dev/vuln/GO-2026-6355"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Will Mortensen"
        }
      ]
    }
  }
}