ubuntu-cve-2021-26937
Vulnerability from osv_ubuntu
Published
2021-02-09 20:15
Modified
2025-09-08 16:47
Summary
Details

encoding.c in GNU Screen through 4.8.0 allows remote attackers to cause a denial of service (invalid write access and application crash) or possibly have unspecified other impact via a crafted UTF-8 character sequence.

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "screen",
            "binary_version": "4.1.0~20120320gitdb59704-9ubuntu0.1~esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "screen",
        "purl": "pkg:deb/ubuntu/screen@4.1.0~20120320gitdb59704-9ubuntu0.1~esm2?arch=source\u0026distro=trusty/esm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.1.0~20120320gitdb59704-9ubuntu0.1~esm2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.0.3-14ubuntu10",
        "4.1.0~20120320gitdb59704-9",
        "4.1.0~20120320gitdb59704-9ubuntu0.1~esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "screen",
            "binary_version": "4.3.1-2ubuntu0.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "screen",
        "purl": "pkg:deb/ubuntu/screen@4.3.1-2ubuntu0.1?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.3.1-2ubuntu0.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.3.1-2",
        "4.3.1-2build1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "screen",
            "binary_version": "4.6.2-1ubuntu1.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "screen",
        "purl": "pkg:deb/ubuntu/screen@4.6.2-1ubuntu1.1?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.6.2-1ubuntu1.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.6.1-1",
        "4.6.2-1",
        "4.6.2-1ubuntu1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "screen",
            "binary_version": "4.8.0-1ubuntu0.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "screen",
        "purl": "pkg:deb/ubuntu/screen@4.8.0-1ubuntu0.1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.8.0-1ubuntu0.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.6.2-3build1",
        "4.7.0-1",
        "4.8.0-1"
      ]
    }
  ],
  "aliases": [],
  "details": "encoding.c in GNU Screen through 4.8.0 allows remote attackers to cause a denial of service (invalid write access and application crash) or possibly have unspecified other impact via a crafted UTF-8 character sequence.",
  "id": "UBUNTU-CVE-2021-26937",
  "modified": "2025-09-08T16:47:02Z",
  "published": "2021-02-09T20:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-26937"
    },
    {
      "type": "REPORT",
      "url": "https://lists.gnu.org/archive/html/screen-devel/2021-02/msg00000.html"
    },
    {
      "type": "REPORT",
      "url": "https://seclists.org/oss-sec/2021/q1/124"
    },
    {
      "type": "REPORT",
      "url": "https://seclists.org/oss-sec/2021/q1/129"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4747-1"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4747-2"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2021-26937"
    }
  ],
  "related": [
    "USN-4747-1",
    "USN-4747-2"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/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-2021-26937"
  ]
}



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