{
  "id": "CVE-2021-34557",
  "sourceIdentifier": "cve@mitre.org",
  "published": "2021-06-10T16:15:08.227",
  "lastModified": "2021-09-21T16:39:09.313",
  "vulnStatus": "Analyzed",
  "descriptions": [
    {
      "lang": "en",
      "value": "XScreenSaver 5.45 can be bypassed if the machine has more than ten disconnectable video outputs. A buffer overflow in update_screen_layout() allows an attacker to bypass the standard screen lock authentication mechanism by crashing XScreenSaver. The attacker must physically disconnect many video outputs."
    },
    {
      "lang": "es",
      "value": "XScreenSaver versi\u00f3n 5.45 puede ser omitido si la m\u00e1quina tiene m\u00e1s de diez salidas de v\u00eddeo desconectables. Un desbordamiento de b\u00fafer en la funci\u00f3n update_screen_layout() permite a un atacante omitir el mecanismo de autenticaci\u00f3n de bloqueo de pantalla est\u00e1ndar, al bloquear a XScreenSaver. El atacante debe desconectar f\u00edsicamente muchas salidas de v\u00eddeo"
    }
  ],
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        "source": "nvd@nist.gov",
        "type": "Primary",
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          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "attackVector": "PHYSICAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH",
          "baseScore": 4.6,
          "baseSeverity": "MEDIUM"
        },
        "exploitabilityScore": 0.9,
        "impactScore": 3.6
      }
    ],
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        "source": "nvd@nist.gov",
        "type": "Primary",
        "cvssData": {
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          "vectorString": "AV:L/AC:L/Au:N/C:N/I:N/A:P",
          "accessVector": "LOCAL",
          "accessComplexity": "LOW",
          "authentication": "NONE",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 2.1
        },
        "baseSeverity": "LOW",
        "exploitabilityScore": 3.9,
        "impactScore": 2.9,
        "acInsufInfo": false,
        "obtainAllPrivilege": false,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
      }
    ]
  },
  "weaknesses": [
    {
      "source": "nvd@nist.gov",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-120"
        }
      ]
    }
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  "references": [
    {
      "url": "http://www.openwall.com/lists/oss-security/2021/06/11/1",
      "source": "cve@mitre.org",
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        "Mailing List",
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      "url": "https://github.com/QubesOS/qubes-issues/issues/6595",
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      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TC4QB7TRS4GS7LDXQQ4PC6J3LVFJYISV/",
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