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GSD-2021-34557

Vulnerability from gsd - Updated: 2023-12-13 01:23
Details
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.
Aliases
Aliases

{
  "GSD": {
    "alias": "CVE-2021-34557",
    "description": "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.",
    "id": "GSD-2021-34557",
    "references": [
      "https://www.suse.com/security/cve/CVE-2021-34557.html",
      "https://advisories.mageia.org/CVE-2021-34557.html"
    ]
  },
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
      "aliases": [
        "CVE-2021-34557"
      ],
      "details": "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.",
      "id": "GSD-2021-34557",
      "modified": "2023-12-13T01:23:14.536486Z",
      "schema_version": "1.4.0"
    }
  },
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        "ASSIGNER": "cve@mitre.org",
        "ID": "CVE-2021-34557",
        "STATE": "PUBLIC"
      },
      "affects": {
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            {
              "product": {
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                  {
                    "product_name": "n/a",
                    "version": {
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                        {
                          "version_value": "n/a"
                        }
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          }
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          {
            "name": "https://github.com/QubesOS/qubes-issues/issues/6595",
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            "url": "https://github.com/QubesOS/qubes-issues/issues/6595"
          },
          {
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          },
          {
            "name": "https://github.com/QubesOS/qubes-xscreensaver/blob/master/0001-Fix-updating-outputs-info.patch",
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            "url": "https://github.com/QubesOS/qubes-xscreensaver/blob/master/0001-Fix-updating-outputs-info.patch"
          },
          {
            "name": "[oss-security] 20210611 Re: XScreenSaver 5.45: Disconnecting a video output can cause XScreenSaver to crash and unlock",
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          },
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          }
        ]
      }
    },
    "nvd.nist.gov": {
      "configurations": {
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        "nodes": [
          {
            "children": [],
            "cpe_match": [
              {
                "cpe23Uri": "cpe:2.3:a:xscreensaver_project:xscreensaver:5.45:*:*:*:*:*:*:*",
                "cpe_name": [],
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              }
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            "operator": "OR"
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            "cpe_match": [
              {
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            }
          ]
        },
        "problemtype": {
          "problemtype_data": [
            {
              "description": [
                {
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                  "value": "CWE-120"
                }
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          ]
        },
        "references": {
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            {
              "name": "https://github.com/QubesOS/qubes-xscreensaver/blob/master/0001-Fix-updating-outputs-info.patch",
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            },
            {
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            },
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            },
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            }
          ]
        }
      },
      "impact": {
        "baseMetricV2": {
          "acInsufInfo": false,
          "cvssV2": {
            "accessComplexity": "LOW",
            "accessVector": "LOCAL",
            "authentication": "NONE",
            "availabilityImpact": "PARTIAL",
            "baseScore": 2.1,
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "vectorString": "AV:L/AC:L/Au:N/C:N/I:N/A:P",
            "version": "2.0"
          },
          "exploitabilityScore": 3.9,
          "impactScore": 2.9,
          "obtainAllPrivilege": false,
          "obtainOtherPrivilege": false,
          "obtainUserPrivilege": false,
          "severity": "LOW",
          "userInteractionRequired": false
        },
        "baseMetricV3": {
          "cvssV3": {
            "attackComplexity": "LOW",
            "attackVector": "PHYSICAL",
            "availabilityImpact": "HIGH",
            "baseScore": 4.6,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 0.9,
          "impactScore": 3.6
        }
      },
      "lastModifiedDate": "2021-09-21T16:39Z",
      "publishedDate": "2021-06-10T16:15Z"
    }
  }
}



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