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UBUNTU-CVE-2018-20020 (CVE-2018-20020)

Vulnerability from osv_ubuntu – Published: 2018-12-19 00:00 – Updated: 2026-05-20 14:50 – Source website
VLAI
Details

LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that can result remote code execution

Severity
9.8 (Critical)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
N/A (UNKNOWN)
medium
References
To clipboard 

{
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          },
          {
            "binary_name": "xtightvncviewer",
            "binary_version": "1:1.3.10-10build1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "tightvnc",
        "purl": "pkg:deb/ubuntu/tightvnc@1:1.3.10-10build1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
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            {
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      ],
      "versions": [
        "1:1.3.10-10",
        "1:1.3.10-10build1"
      ]
    }
  ],
  "aliases": [],
  "details": "LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that can result remote code execution",
  "id": "UBUNTU-CVE-2018-20020",
  "modified": "2026-05-20T14:50:57Z",
  "published": "2018-12-19T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2018-20020"
    },
    {
      "type": "REPORT",
      "url": "https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-030-libvnc-heap-out-of-bound-write/"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-3877-1"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4547-1"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4547-2"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4587-1"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2018-20020"
    }
  ],
  "related": [
    "USN-3877-1",
    "USN-4547-1",
    "USN-4547-2",
    "USN-4587-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2018-20020"
  ]
}



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