{
  "id": "CVE-2021-28543",
  "sourceIdentifier": "cve@mitre.org",
  "published": "2021-03-16T15:15:13.843",
  "lastModified": "2022-06-28T14:11:45.273",
  "vulnStatus": "Analyzed",
  "descriptions": [
    {
      "lang": "en",
      "value": "Varnish varnish-modules before 0.17.1 allows remote attackers to cause a denial of service (daemon restart) in some configurations. This does not affect organizations that only install the Varnish Cache product; however, it is common to install both Varnish Cache and varnish-modules. Specifically, an assertion failure or NULL pointer dereference can be triggered in Varnish Cache through the varnish-modules header.append() and header.copy() functions. For some Varnish Configuration Language (VCL) files, this gives remote clients an opportunity to cause a Varnish Cache restart. A restart reduces overall availability and performance due to an increased number of cache misses, and may cause higher load on backend servers."
    },
    {
      "lang": "es",
      "value": "Varnish varnish-modules versiones anteriores a 0.17.1, permite a atacantes remotos causar una denegaci\u00f3n de servicio (reinicio del demonio) en algunas configuraciones. Esto no afecta a organizaciones que solo instalan el producto Varnish Cache; sin embargo, es com\u00fan instalar tanto Varnish Cache como varnish-modules. Espec\u00edficamente, un error de aserci\u00f3n o desreferencia del puntero NULL se puede activar en Varnish Cache por medio de las funciones header.append() y header.copy() de varnish-modules. Para algunos archivos de Varnish Configuration Language (VCL), esto brinda a clientes remotos la oportunidad de causar un reinicio de Varnish Cache. Un reinicio reduce la disponibilidad y el rendimiento general debido a un mayor n\u00famero de p\u00e9rdidas de cach\u00e9 y puede causar una mayor carga en los servidores de backend"
    }
  ],
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        "source": "nvd@nist.gov",
        "type": "Primary",
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          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6
      },
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        "type": "Secondary",
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          "attackVector": "NETWORK",
          "attackComplexity": "HIGH",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "LOW",
          "baseScore": 4.0,
          "baseSeverity": "MEDIUM"
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        "exploitabilityScore": 2.2,
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        "type": "Primary",
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          "accessVector": "NETWORK",
          "accessComplexity": "LOW",
          "authentication": "NONE",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 5.0
        },
        "baseSeverity": "MEDIUM",
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        "acInsufInfo": false,
        "obtainAllPrivilege": false,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
      }
    ]
  },
  "weaknesses": [
    {
      "source": "nvd@nist.gov",
      "type": "Primary",
      "description": [
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          "lang": "en",
          "value": "CWE-476"
        },
        {
          "lang": "en",
          "value": "CWE-617"
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  "references": [
    {
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/OPFBRQUJNWHCB3GQHSSAPRLQU6Q6PY43/",
      "source": "cve@mitre.org",
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        "Mailing List",
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      "url": "https://varnish-cache.org/security/VSV00006.html",
      "source": "cve@mitre.org",
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}