MediumFix available

shadow — security advisory

Type: advisorySources: OSVAdvisory ID: DEBIAN-CVE-2018-7169

An issue was discovered in shadow 4.5. newgidmap (in shadow-utils) is setuid and allows an unprivileged user to be placed in a user namespace where setgroups(2) is permitted. This allows an attacker to remove themselves from a supplementary group, which may allow access to certain filesystem paths if the administrator has used "group blacklisting" (e.g., chmod g-rwx) to restrict access to paths. This flaw effectively reverts a security feature in the kernel (in particular, the /proc/self/setgroups knob) to prevent this sort of privilege escalation.

Products: shadow
Affected versions: Not specified
Fixed versions: 1:4.7-1
CVEs: CVE-2018-7169
Confirmed fixed CVEs: Not specified
Updated in this feed: 1 Nov 2026, 00:15 UTC · Revision 1

Source evidence

DEBIAN-CVE-2018-7169

core-osv · Original source

Published 15 Feb 2018, 20:29 UTC

osv:DEBIAN-CVE-2018-7169

shadow

Fixed versions: 1:4.7-1

shadow

Fixed versions: 1:4.7-1

shadow

Fixed versions: 1:4.7-1

Complete source record

{
  "id": "a9d942944ea2769e70bfea5f2e7b726087bf3f89a989d0006de25b3763085474",
  "url": "https://osv.dev/vulnerability/DEBIAN-CVE-2018-7169",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "DEBIAN-CVE-2018-7169",
    "summary": "An issue was discovered in shadow 4.5. newgidmap (in shadow-utils) is setuid and allows an unprivileged user to be placed in a user namespace where setgroups(2) is permitted. This allows an attacker to remove themselves from a supplementary group, which may allow access to certain filesystem paths if the administrator has used \"group blacklisting\" (e.g., chmod g-rwx) to restrict access to paths. This flaw effectively reverts a security feature in the kernel (in particular, the /proc/self/setgroups knob) to prevent this sort of privilege escalation.",
    "evidence": "osv:DEBIAN-CVE-2018-7169",
    "products": [
      {
        "name": {
          "value": "shadow",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "1:4.7-1",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      },
      {
        "name": {
          "value": "shadow",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "1:4.7-1",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      },
      {
        "name": {
          "value": "shadow",
          "evidence": "/affected/2/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "1:4.7-1",
            "evidence": "/affected/2/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "DEBIAN-CVE-2018-7169",
      "aliases": [
        "DEBIAN-CVE-2018-7169"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "1:4.7-1"
                }
              ]
            }
          ],
          "package": {
            "name": "shadow",
            "purl": "pkg:deb/debian/shadow?arch=source&distro=bookworm",
            "ecosystem": "Debian:12"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2018-7169.json"
          },
          "ecosystem_specific": {
            "urgency": "low"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "1:4.7-1"
                }
              ]
            }
          ],
          "package": {
            "name": "shadow",
            "purl": "pkg:deb/debian/shadow?arch=source&distro=trixie",
            "ecosystem": "Debian:13"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2018-7169.json"
          },
          "ecosystem_specific": {
            "urgency": "low"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "1:4.7-1"
                }
              ]
            }
          ],
          "package": {
            "name": "shadow",
            "purl": "pkg:deb/debian/shadow?arch=source&distro=forky",
            "ecosystem": "Debian:14"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2018-7169.json"
          },
          "ecosystem_specific": {
            "urgency": "low"
          }
        }
      ],
      "modified": "2026-10-23T18:03:08.102431045Z",
      "provider": "osv",
      "upstream": [
        "CVE-2018-7169"
      ],
      "references": [
        "https://security-tracker.debian.org/tracker/CVE-2018-7169"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2018-7169",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 420535,
  "published_at": "2018-02-15T20:29:00.867+00:00"
}