{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "2.41.5"
              }
            ],
            "source": [
              "DESCRIPTION",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "230de59ffbee328506d92d3534e66d56de1afe5d"
            },
            {
              "fixed": "1d14676ea70003e9f5b2a6a76af0cadb1190411a"
            },
            {
              "fixed": "a15c00a9e545aa8b9cf6ec0f888ff6c7b3eaeedc"
            },
            {
              "fixed": "f57cea130839c0af8dc0525274267ae4cfd66bbf"
            }
          ],
          "repo": "https://github.com/util-linux/util-linux",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-m25x-3hj9-m26f"
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-390"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/76xxx/CVE-2026-76642.json",
    "unresolved_ranges": [
      {
        "extracted_events": [
          {
            "introduced": "2.39"
          },
          {
            "fixed": "2.41.6"
          },
          {
            "introduced": "2.42"
          },
          {
            "fixed": "2.42.3"
          }
        ],
        "source": "AFFECTED_FIELD"
      },
      {
        "extracted_events": [
          {
            "introduced": "2.39"
          },
          {
            "fixed": "2.41.6"
          },
          {
            "introduced": "2.42"
          },
          {
            "fixed": "2.42.3"
          }
        ],
        "source": "CPE_FIELD"
      }
    ]
  },
  "details": "util-linux versions through 2.41.5 and 2.42.2 fail to check mount helper exit status before running post-mount hooks, allowing unprivileged users to execute privileged operations on pre-existing filesystems. Attackers can exploit X-mount.idmap or X-mount.owner hooks to clone filesystems with inherited suid bits or modify target inode permissions after a helper fails, achieving privilege escalation.",
  "id": "CVE-2026-76642",
  "modified": "2026-09-05T03:30:49.745774918Z",
  "published": "2026-09-03T10:54:08.150Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/76xxx/CVE-2026-76642.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/util-linux/util-linux/security/advisories/GHSA-m25x-3hj9-m26f"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-76642"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/util-linux-libmount-privilege-escalation-via-failed-mount-helper"
    },
    {
      "type": "FIX",
      "url": "https://github.com/util-linux/util-linux/commit/1d14676ea70003e9f5b2a6a76af0cadb1190411a"
    },
    {
      "type": "FIX",
      "url": "https://github.com/util-linux/util-linux/commit/a15c00a9e545aa8b9cf6ec0f888ff6c7b3eaeedc"
    },
    {
      "type": "FIX",
      "url": "https://github.com/util-linux/util-linux/commit/f57cea130839c0af8dc0525274267ae4cfd66bbf"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/util-linux/util-linux"
    },
    {
      "type": "ARTICLE",
      "url": "https://github.com/util-linux/util-linux/blob/v2.42.2/libmount/src/context_mount.c#L476"
    },
    {
      "type": "ARTICLE",
      "url": "https://github.com/util-linux/util-linux/blob/v2.42.2/libmount/src/context_mount.c#L892"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "util-linux libmount Privilege Escalation via Failed Mount Helper"
}