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FKIE_CVE-2021-28651

Vulnerability from fkie_nvd - Published: 2021-05-27 12:15 - Updated: 2026-06-17 03:46
Summary
An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to a buffer-management bug, it allows a denial of service. When resolving a request with the urn: scheme, the parser leaks a small amount of memory. However, there is an unspecified attack methodology that can easily trigger a large amount of memory consumption.
References
cve@mitre.orghttp://seclists.org/fulldisclosure/2023/Oct/14Mailing List, Third Party Advisory
cve@mitre.orghttp://www.openwall.com/lists/oss-security/2023/10/11/3Mailing List, Third Party Advisory
cve@mitre.orghttps://bugs.squid-cache.org/show_bug.cgi?id=5104Exploit, Issue Tracking, Vendor Advisory
cve@mitre.orghttps://github.com/squid-cache/squid/security/advisories/GHSA-ch36-9jhx-phm4Patch, Third Party Advisory
cve@mitre.orghttps://lists.debian.org/debian-lts-announce/2021/06/msg00014.htmlMailing List, Third Party Advisory
cve@mitre.orghttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LSQ3U54ZCNXR44QRPW3AV2VCS6K3TKCF/
cve@mitre.orghttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T4EPIWUZDJAXADDHVOPKRBTQHPBR6H66/
cve@mitre.orghttps://security.netapp.com/advisory/ntap-20210716-0007/Third Party Advisory
cve@mitre.orghttps://www.debian.org/security/2021/dsa-4924Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108http://seclists.org/fulldisclosure/2023/Oct/14Mailing List, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2023/10/11/3Mailing List, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://bugs.squid-cache.org/show_bug.cgi?id=5104Exploit, Issue Tracking, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/squid-cache/squid/security/advisories/GHSA-ch36-9jhx-phm4Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2021/06/msg00014.htmlMailing List, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LSQ3U54ZCNXR44QRPW3AV2VCS6K3TKCF/
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T4EPIWUZDJAXADDHVOPKRBTQHPBR6H66/
af854a3a-2127-422b-91ae-364da2661108https://security.netapp.com/advisory/ntap-20210716-0007/Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.debian.org/security/2021/dsa-4924Third Party Advisory

{
  "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:squid-cache:squid:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "CB25C152-063D-4C60-8DA0-A0A0256B2310",
              "versionEndExcluding": "4.15",
              "versionStartIncluding": "2.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "68801A75-0B13-444A-B88F-8BDD4EE953D3",
              "versionEndExcluding": "5.0.6",
              "versionStartIncluding": "5.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "DEECE5FC-CACF-4496-A3E7-164736409252",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "07B237A9-69A3-4A9C-9DA0-4E06BD37AE73",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*",
              "matchCriteriaId": "E460AA51-FCDA-46B9-AE97-E6676AA5E194",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*",
              "matchCriteriaId": "A930E247-0B43-43CB-98FF-6CE7B8189835",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:netapp:cloud_manager:-:*:*:*:*:*:*:*",
              "matchCriteriaId": "197D0D80-6702-4B61-B681-AFDBA7D69067",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to a buffer-management bug, it allows a denial of service. When resolving a request with the urn: scheme, the parser leaks a small amount of memory. However, there is an unspecified attack methodology that can easily trigger a large amount of memory consumption."
    },
    {
      "lang": "es",
      "value": "Se detect\u00f3 un problema en Squid versiones anteriores a 4.15 y versiones 5.x anteriores a 5.0.6.\u0026#xa0;Debido a un bug de administraci\u00f3n del b\u00fafer, permite una denegaci\u00f3n de servicio.\u0026#xa0;Cuando se resuelve una petici\u00f3n con el esquema urn:, el analizador filtra una peque\u00f1a cantidad de memoria.\u0026#xa0;Sin embargo, se presenta una metodolog\u00eda de ataque no especificada que puede desencadenar f\u00e1cilmente una gran cantidad de consumo de memoria"
    }
  ],
  "id": "CVE-2021-28651",
  "lastModified": "2026-06-17T03:46:42.483",
  "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": "2021-05-27T12:15:08.197",
  "references": [
    {
      "source": "cve@mitre.org",
      "tags": [
        "Mailing List",
        "Third Party Advisory"
      ],
      "url": "http://seclists.org/fulldisclosure/2023/Oct/14"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Mailing List",
        "Third Party Advisory"
      ],
      "url": "http://www.openwall.com/lists/oss-security/2023/10/11/3"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Exploit",
        "Issue Tracking",
        "Vendor Advisory"
      ],
      "url": "https://bugs.squid-cache.org/show_bug.cgi?id=5104"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/squid-cache/squid/security/advisories/GHSA-ch36-9jhx-phm4"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Mailing List",
        "Third Party Advisory"
      ],
      "url": "https://lists.debian.org/debian-lts-announce/2021/06/msg00014.html"
    },
    {
      "source": "cve@mitre.org",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LSQ3U54ZCNXR44QRPW3AV2VCS6K3TKCF/"
    },
    {
      "source": "cve@mitre.org",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T4EPIWUZDJAXADDHVOPKRBTQHPBR6H66/"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://security.netapp.com/advisory/ntap-20210716-0007/"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://www.debian.org/security/2021/dsa-4924"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Mailing List",
        "Third Party Advisory"
      ],
      "url": "http://seclists.org/fulldisclosure/2023/Oct/14"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Mailing List",
        "Third Party Advisory"
      ],
      "url": "http://www.openwall.com/lists/oss-security/2023/10/11/3"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Exploit",
        "Issue Tracking",
        "Vendor Advisory"
      ],
      "url": "https://bugs.squid-cache.org/show_bug.cgi?id=5104"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/squid-cache/squid/security/advisories/GHSA-ch36-9jhx-phm4"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Mailing List",
        "Third Party Advisory"
      ],
      "url": "https://lists.debian.org/debian-lts-announce/2021/06/msg00014.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LSQ3U54ZCNXR44QRPW3AV2VCS6K3TKCF/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T4EPIWUZDJAXADDHVOPKRBTQHPBR6H66/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://security.netapp.com/advisory/ntap-20210716-0007/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://www.debian.org/security/2021/dsa-4924"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-401"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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Sightings

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Nomenclature

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