{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.0",
  "cveMetadata": {
    "cveId": "CVE-2021-4239"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc"
      },
      "title": "Weak encryption and denial of service in github.com/flynn/noise",
      "descriptions": [
        {
          "lang": "en",
          "value": "The Noise protocol implementation suffers from weakened cryptographic security after encrypting 2^64 messages, and a potential denial of service attack. After 2^64 (~18.4 quintillion) messages are encrypted with the Encrypt function, the nonce counter will wrap around, causing multiple messages to be encrypted with the same key and nonce. In a separate issue, the Decrypt function increments the nonce state even when it fails to decrypt a message. If an attacker can provide an invalid input to the Decrypt function, this will cause the nonce state to desynchronize between the peers, resulting in a failure to encrypt all subsequent messages."
        }
      ],
      "affected": [
        {
          "vendor": "github.com/flynn/noise",
          "product": "github.com/flynn/noise",
          "collectionURL": "https://pkg.go.dev",
          "packageName": "github.com/flynn/noise",
          "versions": [
            {
              "version": "0",
              "lessThan": "1.0.0",
              "status": "affected",
              "versionType": "semver"
            }
          ],
          "programRoutines": [
            {
              "name": "CipherState.Encrypt"
            },
            {
              "name": "CipherState.Decrypt"
            },
            {
              "name": "symmetricState.EncryptAndHash"
            },
            {
              "name": "HandshakeState.ReadMessage"
            },
            {
              "name": "HandshakeState.WriteMessage"
            },
            {
              "name": "symmetricState.DecryptAndHash"
            }
          ],
          "defaultStatus": "unaffected"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "CWE 400: Uncontrolled Resource Consumption"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://github.com/flynn/noise/pull/44"
        },
        {
          "url": "https://pkg.go.dev/vuln/GO-2022-0425"
        }
      ]
    }
  }
}