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FKIE_CVE-2021-26717

Vulnerability from fkie_nvd - Published: 2021-02-18 20:15 - Updated: 2026-06-17 03:43
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
An issue was discovered in Sangoma Asterisk 16.x before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certified Asterisk before 16.8-cert6. When re-negotiating for T.38, if the initial remote response was delayed just enough, Asterisk would send both audio and T.38 in the SDP. If this happened, and the remote responded with a declined T.38 stream, then Asterisk would crash.
References
cve@mitre.orghttp://packetstormsecurity.com/files/161471/Asterisk-Project-Security-Advisory-AST-2021-002.htmlThird Party Advisory
cve@mitre.orghttp://seclists.org/fulldisclosure/2021/Feb/58Mailing List, Patch, Third Party Advisory
cve@mitre.orghttps://downloads.asterisk.org/pub/security/Vendor Advisory
cve@mitre.orghttps://downloads.asterisk.org/pub/security/AST-2021-002.htmlVendor Advisory
cve@mitre.orghttps://issues.asterisk.org/jira/browse/ASTERISK-29203Issue Tracking, Patch, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108http://packetstormsecurity.com/files/161471/Asterisk-Project-Security-Advisory-AST-2021-002.htmlThird Party Advisory
af854a3a-2127-422b-91ae-364da2661108http://seclists.org/fulldisclosure/2021/Feb/58Mailing List, Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://downloads.asterisk.org/pub/security/Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://downloads.asterisk.org/pub/security/AST-2021-002.htmlVendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://issues.asterisk.org/jira/browse/ASTERISK-29203Issue Tracking, Patch, Vendor Advisory
Impacted products
Vendor Product Version
digium asterisk *
digium asterisk *
digium asterisk *
digium certified_asterisk 16.8
digium certified_asterisk 16.8
digium certified_asterisk 16.8
digium certified_asterisk 16.8
digium certified_asterisk 16.8
digium certified_asterisk 16.8
digium certified_asterisk 16.8
digium certified_asterisk 16.8
digium certified_asterisk 16.8
digium certified_asterisk 16.8
digium certified_asterisk 16.8
digium certified_asterisk 16.8
digium certified_asterisk 16.8
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:digium:asterisk:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "7382B641-0396-456F-BF33-3F6412E35F2D",
              "versionEndExcluding": "16.16.1",
              "versionStartIncluding": "16.0.0",
              "vulnerable": true
            },
            {
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              "matchCriteriaId": "C5BA8606-ADA9-4841-A7E2-A9165138849A",
              "versionEndExcluding": "17.9.2",
              "versionStartIncluding": "17.0.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:digium:asterisk:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "F10CB148-DF9C-4134-A417-3B111C036E20",
              "versionEndExcluding": "18.2.1",
              "versionStartIncluding": "18.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:digium:certified_asterisk:16.8:-:*:*:*:*:*:*",
              "matchCriteriaId": "81C3E390-8B99-4EB8-82DD-02893611209A",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:digium:certified_asterisk:16.8:cert1-rc1:*:*:*:*:*:*",
              "matchCriteriaId": "17DB2297-1908-4F87-8046-2BAA74569D71",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:digium:certified_asterisk:16.8:cert1-rc2:*:*:*:*:*:*",
              "matchCriteriaId": "CEA2CC40-C2F6-4828-82F0-1B50D3E61F77",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:digium:certified_asterisk:16.8:cert1-rc3:*:*:*:*:*:*",
              "matchCriteriaId": "32F19F43-C1E8-4B6C-9356-AF355B7320BD",
              "vulnerable": true
            },
            {
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              "matchCriteriaId": "21D1FA32-B441-485F-8AE9-F3A394626909",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:digium:certified_asterisk:16.8:cert2:*:*:*:*:*:*",
              "matchCriteriaId": "F7795CCF-B160-4B4F-9529-1192C11D7FDB",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:digium:certified_asterisk:16.8:cert3:*:*:*:*:*:*",
              "matchCriteriaId": "0C5E5D0D-9EB3-40FD-8B7E-E93A95D07AB1",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:digium:certified_asterisk:16.8:cert4:*:*:*:*:*:*",
              "matchCriteriaId": "C7DFDA30-DD61-4BBC-AFE4-448BF2A4F303",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:digium:certified_asterisk:16.8:cert4-rc1:*:*:*:*:*:*",
              "matchCriteriaId": "142F1F89-49AC-4A0B-A273-61F697063A5A",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:digium:certified_asterisk:16.8:cert4-rc2:*:*:*:*:*:*",
              "matchCriteriaId": "53041795-788C-4914-A2F6-41539ABE0244",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:digium:certified_asterisk:16.8:cert4-rc3:*:*:*:*:*:*",
              "matchCriteriaId": "FBB98E65-B2D0-49A4-8BF3-12155E3E13C9",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:digium:certified_asterisk:16.8:cert4-rc4:*:*:*:*:*:*",
              "matchCriteriaId": "769C854C-03CD-40A9-B39B-C0CDCA8252EA",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:digium:certified_asterisk:16.8:cert5:*:*:*:*:*:*",
              "matchCriteriaId": "6D86AD6E-4E07-48B0-88D8-E18F277FFE6A",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "An issue was discovered in Sangoma Asterisk 16.x before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certified Asterisk before 16.8-cert6. When re-negotiating for T.38, if the initial remote response was delayed just enough, Asterisk would send both audio and T.38 in the SDP. If this happened, and the remote responded with a declined T.38 stream, then Asterisk would crash."
    },
    {
      "lang": "es",
      "value": "Se detect\u00f3 un problema en Sangoma Asterisk versiones 16.x anteriores a 16.16.1, versiones 17.x anteriores a 17.9.2 y versiones 18.x anteriores a 18.2.1 y Certified Asterisk versiones anteriores a  16.8-cert6.\u0026#xa0;Al renegociar para T.38, si la respuesta remota inicial se retras\u00f3 lo suficiente, Asterisk enviar\u00eda tanto audio como T.38 en el SDP.\u0026#xa0;Si esto sucediera, y el control remoto respondiera con una transmisi\u00f3n T.38 rechazada, entonces Asterisk podr\u00eda bloquearse"
    }
  ],
  "id": "CVE-2021-26717",
  "lastModified": "2026-06-17T03:43:42.950",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 5.0,
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
          "version": "2.0"
        },
        "exploitabilityScore": 10.0,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-02-18T20:15:12.667",
  "references": [
    {
      "source": "cve@mitre.org",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "http://packetstormsecurity.com/files/161471/Asterisk-Project-Security-Advisory-AST-2021-002.html"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Mailing List",
        "Patch",
        "Third Party Advisory"
      ],
      "url": "http://seclists.org/fulldisclosure/2021/Feb/58"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://downloads.asterisk.org/pub/security/"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://downloads.asterisk.org/pub/security/AST-2021-002.html"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Issue Tracking",
        "Patch",
        "Vendor Advisory"
      ],
      "url": "https://issues.asterisk.org/jira/browse/ASTERISK-29203"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "http://packetstormsecurity.com/files/161471/Asterisk-Project-Security-Advisory-AST-2021-002.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
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        "Patch",
        "Third Party Advisory"
      ],
      "url": "http://seclists.org/fulldisclosure/2021/Feb/58"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://downloads.asterisk.org/pub/security/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
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      ],
      "url": "https://downloads.asterisk.org/pub/security/AST-2021-002.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Issue Tracking",
        "Patch",
        "Vendor Advisory"
      ],
      "url": "https://issues.asterisk.org/jira/browse/ASTERISK-29203"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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