ubuntu-cve-2019-18634
Vulnerability from osv_ubuntu
Published
2020-01-31 00:00
Modified
2025-09-08 16:45
Summary
Details

In Sudo before 1.8.26, if pwfeedback is enabled in /etc/sudoers, users can trigger a stack-based buffer overflow in the privileged sudo process. (pwfeedback is a default setting in Linux Mint and elementary OS; however, it is NOT the default for upstream and many other packages, and would exist only if enabled by an administrator.) The attacker needs to deliver a long string to the stdin of getln() in tgetpass.c.

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)
low
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "sudo",
            "binary_version": "1.8.9p5-1ubuntu1.5+esm3"
          },
          {
            "binary_name": "sudo-ldap",
            "binary_version": "1.8.9p5-1ubuntu1.5+esm3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "sudo",
        "purl": "pkg:deb/ubuntu/sudo@1.8.9p5-1ubuntu1.5+esm3?arch=source\u0026distro=trusty/esm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.8.9p5-1ubuntu1.5+esm3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.8.6p3-0ubuntu3",
        "1.8.8-2ubuntu1",
        "1.8.8-2ubuntu2",
        "1.8.9p4-1ubuntu1",
        "1.8.9p4-1ubuntu2",
        "1.8.9p5-1ubuntu1",
        "1.8.9p5-1ubuntu1.1",
        "1.8.9p5-1ubuntu1.2",
        "1.8.9p5-1ubuntu1.3",
        "1.8.9p5-1ubuntu1.4",
        "1.8.9p5-1ubuntu1.5+esm1",
        "1.8.9p5-1ubuntu1.5+esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "sudo",
            "binary_version": "1.8.16-0ubuntu1.9"
          },
          {
            "binary_name": "sudo-ldap",
            "binary_version": "1.8.16-0ubuntu1.9"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "sudo",
        "purl": "pkg:deb/ubuntu/sudo@1.8.16-0ubuntu1.9?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.8.16-0ubuntu1.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.8.12-1ubuntu3",
        "1.8.16-0ubuntu1",
        "1.8.16-0ubuntu1.1",
        "1.8.16-0ubuntu1.2",
        "1.8.16-0ubuntu1.3",
        "1.8.16-0ubuntu1.4",
        "1.8.16-0ubuntu1.5",
        "1.8.16-0ubuntu1.6",
        "1.8.16-0ubuntu1.7",
        "1.8.16-0ubuntu1.8"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "sudo",
            "binary_version": "1.8.21p2-3ubuntu1.2"
          },
          {
            "binary_name": "sudo-ldap",
            "binary_version": "1.8.21p2-3ubuntu1.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "sudo",
        "purl": "pkg:deb/ubuntu/sudo@1.8.21p2-3ubuntu1.2?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.8.21p2-3ubuntu1.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.8.20p2-1ubuntu1",
        "1.8.21p2-2ubuntu1",
        "1.8.21p2-3ubuntu1",
        "1.8.21p2-3ubuntu1.1"
      ]
    }
  ],
  "aliases": [],
  "details": "In Sudo before 1.8.26, if pwfeedback is enabled in /etc/sudoers, users can trigger a stack-based buffer overflow in the privileged sudo process. (pwfeedback is a default setting in Linux Mint and elementary OS; however, it is NOT the default for upstream and many other packages, and would exist only if enabled by an administrator.) The attacker needs to deliver a long string to the stdin of getln() in tgetpass.c.",
  "id": "UBUNTU-CVE-2019-18634",
  "modified": "2025-09-08T16:45:39Z",
  "published": "2020-01-31T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2019-18634"
    },
    {
      "type": "REPORT",
      "url": "https://www.openwall.com/lists/oss-security/2020/01/30/6"
    },
    {
      "type": "REPORT",
      "url": "https://www.openwall.com/lists/oss-security/2020/01/31/1"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4263-1"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4263-2"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2019-18634"
    }
  ],
  "related": [
    "USN-4263-1",
    "USN-4263-2"
  ],
  "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": "low",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2019-18634"
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.