ubuntu-cve-2017-20002
Vulnerability from osv_ubuntu
Published
2021-03-17 06:15
Modified
2025-07-16 04:53
Summary
Details

The Debian shadow package before 1:4.5-1 for Shadow incorrectly lists pts/0 and pts/1 as physical terminals in /etc/securetty. This allows local users to login as password-less users even if they are connected by non-physical means such as SSH (hence bypassing PAM's nullok_secure configuration). This notably affects environments such as virtual machines automatically generated with a default blank root password, allowing all local users to escalate privileges.

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

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "login",
            "binary_version": "1:4.2-3.1ubuntu5.4"
          },
          {
            "binary_name": "login-dbgsym",
            "binary_version": "1:4.2-3.1ubuntu5.4"
          },
          {
            "binary_name": "passwd",
            "binary_version": "1:4.2-3.1ubuntu5.4"
          },
          {
            "binary_name": "passwd-dbgsym",
            "binary_version": "1:4.2-3.1ubuntu5.4"
          },
          {
            "binary_name": "uidmap",
            "binary_version": "1:4.2-3.1ubuntu5.4"
          },
          {
            "binary_name": "uidmap-dbgsym",
            "binary_version": "1:4.2-3.1ubuntu5.4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "shadow",
        "purl": "pkg:deb/ubuntu/shadow@1:4.2-3.1ubuntu5.4?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:4.2-3.1ubuntu5.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:4.1.5.1-1.1ubuntu7",
        "1:4.2-3.1ubuntu1",
        "1:4.2-3.1ubuntu2",
        "1:4.2-3.1ubuntu3",
        "1:4.2-3.1ubuntu4",
        "1:4.2-3.1ubuntu5",
        "1:4.2-3.1ubuntu5.2",
        "1:4.2-3.1ubuntu5.3"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "login",
            "binary_version": "1:4.5-1ubuntu2"
          },
          {
            "binary_name": "login-dbgsym",
            "binary_version": "1:4.5-1ubuntu2"
          },
          {
            "binary_name": "passwd",
            "binary_version": "1:4.5-1ubuntu2"
          },
          {
            "binary_name": "passwd-dbgsym",
            "binary_version": "1:4.5-1ubuntu2"
          },
          {
            "binary_name": "uidmap",
            "binary_version": "1:4.5-1ubuntu2"
          },
          {
            "binary_name": "uidmap-dbgsym",
            "binary_version": "1:4.5-1ubuntu2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "shadow",
        "purl": "pkg:deb/ubuntu/shadow@1:4.5-1ubuntu2?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:4.5-1ubuntu2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:4.2-3.2ubuntu4",
        "1:4.5-1ubuntu1"
      ]
    }
  ],
  "aliases": [],
  "details": "The Debian shadow package before 1:4.5-1 for Shadow incorrectly lists pts/0 and pts/1 as physical terminals in /etc/securetty. This allows local users to login as password-less users even if they are connected by non-physical means such as SSH (hence bypassing PAM\u0027s nullok_secure configuration). This notably affects environments such as virtual machines automatically generated with a default blank root password, allowing all local users to escalate privileges.",
  "id": "UBUNTU-CVE-2017-20002",
  "modified": "2025-07-16T04:53:19Z",
  "published": "2021-03-17T06:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2017-20002"
    },
    {
      "type": "REPORT",
      "url": "https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=877374"
    },
    {
      "type": "REPORT",
      "url": "https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=914957"
    },
    {
      "type": "REPORT",
      "url": "https://lists.debian.org/debian-lts-announce/2021/03/msg00020.html"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2017-20002"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2017-20002"
  ],
  "withdrawn": "2025-07-18T16:44:19Z"
}



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