FKIE_CVE-2021-3716

Vulnerability from fkie_nvd - Published: 2022-03-02 23:15 - Updated: 2026-06-17 04:05
Severity
3.1 (Low) - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
Summary
A flaw was found in nbdkit due to to improperly caching plaintext state across the STARTTLS encryption boundary. A MitM attacker could use this flaw to inject a plaintext NBD_OPT_STRUCTURED_REPLY before proxying everything else a client sends to the server, potentially leading the client to terminate the NBD session. The highest threat from this vulnerability is to system availability.
References
secalert@redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=1994695Issue Tracking, Patch, Third Party Advisory
secalert@redhat.comhttps://gitlab.com/nbdkit/nbdkit/-/commit/09a13dafb7bb3a38ab52eb5501cba786365ba7fdPatch, Third Party Advisory
secalert@redhat.comhttps://gitlab.com/nbdkit/nbdkit/-/commit/6c5faac6a37077cf2366388a80862bb00616d0d8Patch, Third Party Advisory
secalert@redhat.comhttps://listman.redhat.com/archives/libguestfs/2021-August/msg00083.htmlBroken Link
secalert@redhat.comhttps://www.openwall.com/lists/oss-security/2021/08/18/2Mailing List, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://bugzilla.redhat.com/show_bug.cgi?id=1994695Issue Tracking, Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://gitlab.com/nbdkit/nbdkit/-/commit/09a13dafb7bb3a38ab52eb5501cba786365ba7fdPatch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://gitlab.com/nbdkit/nbdkit/-/commit/6c5faac6a37077cf2366388a80862bb00616d0d8Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://listman.redhat.com/archives/libguestfs/2021-August/msg00083.htmlBroken Link
af854a3a-2127-422b-91ae-364da2661108https://www.openwall.com/lists/oss-security/2021/08/18/2Mailing List, Third Party Advisory
Impacted products
Vendor Product Version
nbdkit_project nbdkit *
nbdkit_project nbdkit *
nbdkit_project nbdkit *
redhat enterprise_linux 8.0
redhat enterprise_linux 8.0
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "nbdkit",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "Affects nbdkit v1.12 through v1.26.4 | Fixedin nbdkit v1.26.5"
            }
          ]
        }
      ],
      "source": "secalert@redhat.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
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              "criteria": "cpe:2.3:a:nbdkit_project:nbdkit:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "6C81BB5D-5E76-4AB3-A288-ECE78DFC5EF7",
              "versionEndExcluding": "1.24.6",
              "versionStartIncluding": "1.11.8",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:nbdkit_project:nbdkit:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "18CC5957-0C63-4B74-87B8-FA2FA295D9C9",
              "versionEndExcluding": "1.26.5",
              "versionStartIncluding": "1.25.1",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:nbdkit_project:nbdkit:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "50D0C2C5-DE56-4295-80D5-D985775EBC2F",
              "versionEndExcluding": "1.27.6",
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              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:-:*:*:*",
              "matchCriteriaId": "053C1B35-3869-41C2-9551-044182DE0A64",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:advanced_virtualization:*:*:*",
              "matchCriteriaId": "3AA08768-75AF-4791-B229-AE938C780959",
              "vulnerable": true
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          "negate": false,
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  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A flaw was found in nbdkit due to to improperly caching plaintext state across the STARTTLS encryption boundary. A MitM attacker could use this flaw to inject a plaintext NBD_OPT_STRUCTURED_REPLY before proxying everything else a client sends to the server, potentially leading the client to terminate the NBD session. The highest threat from this vulnerability is to system availability."
    },
    {
      "lang": "es",
      "value": "Se ha encontrado un fallo en nbdkit debido al almacenamiento inapropiado en cach\u00e9 del estado de texto plano a trav\u00e9s del l\u00edmite de cifrado STARTTLS. Un atacante de tipo MitM podr\u00eda usar este fallo para inyectar un texto plano NBD_OPT_STRUCTURED_REPLY antes de hacer proxy todo lo dem\u00e1s que un cliente env\u00eda al servidor, lo que podr\u00eda conllevar a que el cliente termine la sesi\u00f3n NBD. La mayor amenaza de esta vulnerabilidad es la disponibilidad del sistema"
    }
  ],
  "id": "CVE-2021-3716",
  "lastModified": "2026-06-17T04:05:37.720",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "LOW",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "NETWORK",
          "authentication": "SINGLE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 3.5,
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "vectorString": "AV:N/AC:M/Au:S/C:N/I:N/A:P",
          "version": "2.0"
        },
        "exploitabilityScore": 6.8,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
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        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 3.1,
          "baseSeverity": "LOW",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L",
          "version": "3.1"
        },
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        "impactScore": 1.4,
        "source": "nvd@nist.gov",
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  },
  "published": "2022-03-02T23:15:09.013",
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    },
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  ],
  "sourceIdentifier": "secalert@redhat.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-924"
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      ],
      "source": "secalert@redhat.com",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-Other"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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