Vulnerability-Lookup

OESA-2026-2211 (CVE-2026-27456)

Vulnerability from osv_openeuler – Published: 2026-05-09 11:11 – Updated: 2026-08-06 11:11 – Source website

Summary

util-linux security update

Details

The util-linux package contains a random collection of files that implements some low-level basic linux utilities.

Security Fix(es):

util-linux is a random collection of Linux utilities. Prior to version 2.41.4, a TOCTOU (Time-of-Check-Time-of-Use) vulnerability has been identified in the SUID binary /usr/bin/mount from util-linux. The mount binary, when setting up loop devices, validates the source file path with user privileges via fork() + setuid() + realpath(), but subsequently re-canonicalizes and opens it with root privileges (euid=0) without verifying that the path has not been replaced between both operations. Neither O_NOFOLLOW, nor inode comparison, nor post-open fstat() are employed. This allows a local unprivileged user to replace the source file with a symlink pointing to any root-owned file or device during the race window, causing the SUID binary to open and mount it as root. Exploitation requires an /etc/fstab entry with user,loop options whose path points to a directory where the attacker has write permission, and that /usr/bin/mount has the SUID bit set (the default configuration on virtually all Linux distributions). The impact is unauthorized read access to root-protected files and block devices, including backup images, disk volumes, and any file containing a valid filesystem. This issue has been patched in version 2.41.4.(CVE-2026-27456)

Severity

4.7 (Medium)


                    
                      CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

References

URL

Type

	https://www.openeuler.org/zh/security/security-bu…	ADVISORY
	https://nvd.nist.gov/vuln/detail/CVE-2026-27456	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "libblkid-2.35.2-29.oe2003sp4.aarch64.rpm",
          "libfdisk-2.35.2-29.oe2003sp4.aarch64.rpm",
          "libmount-2.35.2-29.oe2003sp4.aarch64.rpm",
          "libsmartcols-2.35.2-29.oe2003sp4.aarch64.rpm",
          "libuuid-2.35.2-29.oe2003sp4.aarch64.rpm",
          "python-libmount-2.35.2-29.oe2003sp4.aarch64.rpm",
          "util-linux-2.35.2-29.oe2003sp4.aarch64.rpm",
          "util-linux-debuginfo-2.35.2-29.oe2003sp4.aarch64.rpm",
          "util-linux-debugsource-2.35.2-29.oe2003sp4.aarch64.rpm",
          "util-linux-devel-2.35.2-29.oe2003sp4.aarch64.rpm",
          "util-linux-user-2.35.2-29.oe2003sp4.aarch64.rpm",
          "uuidd-2.35.2-29.oe2003sp4.aarch64.rpm"
        ],
        "noarch": [
          "util-linux-help-2.35.2-29.oe2003sp4.noarch.rpm"
        ],
        "src": [
          "util-linux-2.35.2-29.oe2003sp4.src.rpm"
        ],
        "x86_64": [
          "libblkid-2.35.2-29.oe2003sp4.x86_64.rpm",
          "libfdisk-2.35.2-29.oe2003sp4.x86_64.rpm",
          "libmount-2.35.2-29.oe2003sp4.x86_64.rpm",
          "libsmartcols-2.35.2-29.oe2003sp4.x86_64.rpm",
          "libuuid-2.35.2-29.oe2003sp4.x86_64.rpm",
          "python-libmount-2.35.2-29.oe2003sp4.x86_64.rpm",
          "util-linux-2.35.2-29.oe2003sp4.x86_64.rpm",
          "util-linux-debuginfo-2.35.2-29.oe2003sp4.x86_64.rpm",
          "util-linux-debugsource-2.35.2-29.oe2003sp4.x86_64.rpm",
          "util-linux-devel-2.35.2-29.oe2003sp4.x86_64.rpm",
          "util-linux-user-2.35.2-29.oe2003sp4.x86_64.rpm",
          "uuidd-2.35.2-29.oe2003sp4.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:20.03-LTS-SP4",
        "name": "util-linux",
        "purl": "pkg:rpm/openEuler/util-linux\u0026distro=openEuler-20.03-LTS-SP4"
      },
      "ranges": [
        {
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            {
              "introduced": "0"
            },
            {
              "fixed": "2.35.2-29.oe2003sp4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
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          "libblkid-2.37.2-52.oe2203sp4.aarch64.rpm",
          "libfdisk-2.37.2-52.oe2203sp4.aarch64.rpm",
          "libmount-2.37.2-52.oe2203sp4.aarch64.rpm",
          "libsmartcols-2.37.2-52.oe2203sp4.aarch64.rpm",
          "libuuid-2.37.2-52.oe2203sp4.aarch64.rpm",
          "python3-libmount-2.37.2-52.oe2203sp4.aarch64.rpm",
          "util-linux-2.37.2-52.oe2203sp4.aarch64.rpm",
          "util-linux-debuginfo-2.37.2-52.oe2203sp4.aarch64.rpm",
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        ],
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        ],
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          "libfdisk-2.37.2-52.oe2203sp4.x86_64.rpm",
          "libmount-2.37.2-52.oe2203sp4.x86_64.rpm",
          "libsmartcols-2.37.2-52.oe2203sp4.x86_64.rpm",
          "libuuid-2.37.2-52.oe2203sp4.x86_64.rpm",
          "python3-libmount-2.37.2-52.oe2203sp4.x86_64.rpm",
          "util-linux-2.37.2-52.oe2203sp4.x86_64.rpm",
          "util-linux-debuginfo-2.37.2-52.oe2203sp4.x86_64.rpm",
          "util-linux-debugsource-2.37.2-52.oe2203sp4.x86_64.rpm",
          "util-linux-devel-2.37.2-52.oe2203sp4.x86_64.rpm",
          "util-linux-user-2.37.2-52.oe2203sp4.x86_64.rpm",
          "uuidd-2.37.2-52.oe2203sp4.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:22.03-LTS-SP4",
        "name": "util-linux",
        "purl": "pkg:rpm/openEuler/util-linux\u0026distro=openEuler-22.03-LTS-SP4"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.37.2-52.oe2203sp4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "aarch64": [
          "libblkid-2.39.1-38.oe2403.aarch64.rpm",
          "libfdisk-2.39.1-38.oe2403.aarch64.rpm",
          "libmount-2.39.1-38.oe2403.aarch64.rpm",
          "libsmartcols-2.39.1-38.oe2403.aarch64.rpm",
          "libuuid-2.39.1-38.oe2403.aarch64.rpm",
          "python3-libmount-2.39.1-38.oe2403.aarch64.rpm",
          "util-linux-2.39.1-38.oe2403.aarch64.rpm",
          "util-linux-debuginfo-2.39.1-38.oe2403.aarch64.rpm",
          "util-linux-debugsource-2.39.1-38.oe2403.aarch64.rpm",
          "util-linux-devel-2.39.1-38.oe2403.aarch64.rpm",
          "util-linux-user-2.39.1-38.oe2403.aarch64.rpm",
          "uuidd-2.39.1-38.oe2403.aarch64.rpm",
          "libblkid-2.39.1-38.oe2403sp1.aarch64.rpm",
          "libfdisk-2.39.1-38.oe2403sp1.aarch64.rpm",
          "libmount-2.39.1-38.oe2403sp1.aarch64.rpm",
          "libsmartcols-2.39.1-38.oe2403sp1.aarch64.rpm",
          "libuuid-2.39.1-38.oe2403sp1.aarch64.rpm",
          "python3-libmount-2.39.1-38.oe2403sp1.aarch64.rpm",
          "util-linux-2.39.1-38.oe2403sp1.aarch64.rpm",
          "util-linux-debuginfo-2.39.1-38.oe2403sp1.aarch64.rpm",
          "util-linux-debugsource-2.39.1-38.oe2403sp1.aarch64.rpm",
          "util-linux-devel-2.39.1-38.oe2403sp1.aarch64.rpm",
          "util-linux-user-2.39.1-38.oe2403sp1.aarch64.rpm",
          "uuidd-2.39.1-38.oe2403sp1.aarch64.rpm",
          "libblkid-2.39.1-38.oe2403sp3.aarch64.rpm",
          "libfdisk-2.39.1-38.oe2403sp3.aarch64.rpm",
          "libmount-2.39.1-38.oe2403sp3.aarch64.rpm",
          "libsmartcols-2.39.1-38.oe2403sp3.aarch64.rpm",
          "libuuid-2.39.1-38.oe2403sp3.aarch64.rpm",
          "python3-libmount-2.39.1-38.oe2403sp3.aarch64.rpm",
          "util-linux-2.39.1-38.oe2403sp3.aarch64.rpm",
          "util-linux-debuginfo-2.39.1-38.oe2403sp3.aarch64.rpm",
          "util-linux-debugsource-2.39.1-38.oe2403sp3.aarch64.rpm",
          "util-linux-devel-2.39.1-38.oe2403sp3.aarch64.rpm",
          "util-linux-user-2.39.1-38.oe2403sp3.aarch64.rpm",
          "uuidd-2.39.1-38.oe2403sp3.aarch64.rpm"
        ],
        "noarch": [
          "util-linux-help-2.39.1-38.oe2403.noarch.rpm",
          "util-linux-help-2.39.1-38.oe2403sp1.noarch.rpm",
          "util-linux-help-2.39.1-38.oe2403sp3.noarch.rpm"
        ],
        "src": [
          "util-linux-2.39.1-38.oe2403.src.rpm",
          "util-linux-2.39.1-38.oe2403sp1.src.rpm",
          "util-linux-2.39.1-38.oe2403sp3.src.rpm"
        ],
        "x86_64": [
          "libblkid-2.39.1-38.oe2403.x86_64.rpm",
          "libfdisk-2.39.1-38.oe2403.x86_64.rpm",
          "libmount-2.39.1-38.oe2403.x86_64.rpm",
          "libsmartcols-2.39.1-38.oe2403.x86_64.rpm",
          "libuuid-2.39.1-38.oe2403.x86_64.rpm",
          "python3-libmount-2.39.1-38.oe2403.x86_64.rpm",
          "util-linux-2.39.1-38.oe2403.x86_64.rpm",
          "util-linux-debuginfo-2.39.1-38.oe2403.x86_64.rpm",
          "util-linux-debugsource-2.39.1-38.oe2403.x86_64.rpm",
          "util-linux-devel-2.39.1-38.oe2403.x86_64.rpm",
          "util-linux-user-2.39.1-38.oe2403.x86_64.rpm",
          "uuidd-2.39.1-38.oe2403.x86_64.rpm",
          "libblkid-2.39.1-38.oe2403sp1.x86_64.rpm",
          "libfdisk-2.39.1-38.oe2403sp1.x86_64.rpm",
          "libmount-2.39.1-38.oe2403sp1.x86_64.rpm",
          "libsmartcols-2.39.1-38.oe2403sp1.x86_64.rpm",
          "libuuid-2.39.1-38.oe2403sp1.x86_64.rpm",
          "python3-libmount-2.39.1-38.oe2403sp1.x86_64.rpm",
          "util-linux-2.39.1-38.oe2403sp1.x86_64.rpm",
          "util-linux-debuginfo-2.39.1-38.oe2403sp1.x86_64.rpm",
          "util-linux-debugsource-2.39.1-38.oe2403sp1.x86_64.rpm",
          "util-linux-devel-2.39.1-38.oe2403sp1.x86_64.rpm",
          "util-linux-user-2.39.1-38.oe2403sp1.x86_64.rpm",
          "uuidd-2.39.1-38.oe2403sp1.x86_64.rpm",
          "libblkid-2.39.1-38.oe2403sp3.x86_64.rpm",
          "libfdisk-2.39.1-38.oe2403sp3.x86_64.rpm",
          "libmount-2.39.1-38.oe2403sp3.x86_64.rpm",
          "libsmartcols-2.39.1-38.oe2403sp3.x86_64.rpm",
          "libuuid-2.39.1-38.oe2403sp3.x86_64.rpm",
          "python3-libmount-2.39.1-38.oe2403sp3.x86_64.rpm",
          "util-linux-2.39.1-38.oe2403sp3.x86_64.rpm",
          "util-linux-debuginfo-2.39.1-38.oe2403sp3.x86_64.rpm",
          "util-linux-debugsource-2.39.1-38.oe2403sp3.x86_64.rpm",
          "util-linux-devel-2.39.1-38.oe2403sp3.x86_64.rpm",
          "util-linux-user-2.39.1-38.oe2403sp3.x86_64.rpm",
          "uuidd-2.39.1-38.oe2403sp3.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS",
        "name": "util-linux",
        "purl": "pkg:rpm/openEuler/util-linux\u0026distro=openEuler-24.03-LTS"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.39.1-38.oe2403sp3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "aarch64": [
          "libblkid-2.39.1-38.oe2403sp1.aarch64.rpm",
          "libfdisk-2.39.1-38.oe2403sp1.aarch64.rpm",
          "libmount-2.39.1-38.oe2403sp1.aarch64.rpm",
          "libsmartcols-2.39.1-38.oe2403sp1.aarch64.rpm",
          "libuuid-2.39.1-38.oe2403sp1.aarch64.rpm",
          "python3-libmount-2.39.1-38.oe2403sp1.aarch64.rpm",
          "util-linux-2.39.1-38.oe2403sp1.aarch64.rpm",
          "util-linux-debuginfo-2.39.1-38.oe2403sp1.aarch64.rpm",
          "util-linux-debugsource-2.39.1-38.oe2403sp1.aarch64.rpm",
          "util-linux-devel-2.39.1-38.oe2403sp1.aarch64.rpm",
          "util-linux-user-2.39.1-38.oe2403sp1.aarch64.rpm",
          "uuidd-2.39.1-38.oe2403sp1.aarch64.rpm"
        ],
        "noarch": [
          "util-linux-help-2.39.1-38.oe2403sp1.noarch.rpm"
        ],
        "src": [
          "util-linux-2.39.1-38.oe2403sp1.src.rpm"
        ],
        "x86_64": [
          "libblkid-2.39.1-38.oe2403sp1.x86_64.rpm",
          "libfdisk-2.39.1-38.oe2403sp1.x86_64.rpm",
          "libmount-2.39.1-38.oe2403sp1.x86_64.rpm",
          "libsmartcols-2.39.1-38.oe2403sp1.x86_64.rpm",
          "libuuid-2.39.1-38.oe2403sp1.x86_64.rpm",
          "python3-libmount-2.39.1-38.oe2403sp1.x86_64.rpm",
          "util-linux-2.39.1-38.oe2403sp1.x86_64.rpm",
          "util-linux-debuginfo-2.39.1-38.oe2403sp1.x86_64.rpm",
          "util-linux-debugsource-2.39.1-38.oe2403sp1.x86_64.rpm",
          "util-linux-devel-2.39.1-38.oe2403sp1.x86_64.rpm",
          "util-linux-user-2.39.1-38.oe2403sp1.x86_64.rpm",
          "uuidd-2.39.1-38.oe2403sp1.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP1",
        "name": "util-linux",
        "purl": "pkg:rpm/openEuler/util-linux\u0026distro=openEuler-24.03-LTS-SP1"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.39.1-38.oe2403sp1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "aarch64": [
          "libblkid-2.39.1-38.oe2403sp3.aarch64.rpm",
          "libfdisk-2.39.1-38.oe2403sp3.aarch64.rpm",
          "libmount-2.39.1-38.oe2403sp3.aarch64.rpm",
          "libsmartcols-2.39.1-38.oe2403sp3.aarch64.rpm",
          "libuuid-2.39.1-38.oe2403sp3.aarch64.rpm",
          "python3-libmount-2.39.1-38.oe2403sp3.aarch64.rpm",
          "util-linux-2.39.1-38.oe2403sp3.aarch64.rpm",
          "util-linux-debuginfo-2.39.1-38.oe2403sp3.aarch64.rpm",
          "util-linux-debugsource-2.39.1-38.oe2403sp3.aarch64.rpm",
          "util-linux-devel-2.39.1-38.oe2403sp3.aarch64.rpm",
          "util-linux-user-2.39.1-38.oe2403sp3.aarch64.rpm",
          "uuidd-2.39.1-38.oe2403sp3.aarch64.rpm"
        ],
        "noarch": [
          "util-linux-help-2.39.1-38.oe2403sp3.noarch.rpm"
        ],
        "src": [
          "util-linux-2.39.1-38.oe2403sp3.src.rpm"
        ],
        "x86_64": [
          "libblkid-2.39.1-38.oe2403sp3.x86_64.rpm",
          "libfdisk-2.39.1-38.oe2403sp3.x86_64.rpm",
          "libmount-2.39.1-38.oe2403sp3.x86_64.rpm",
          "libsmartcols-2.39.1-38.oe2403sp3.x86_64.rpm",
          "libuuid-2.39.1-38.oe2403sp3.x86_64.rpm",
          "python3-libmount-2.39.1-38.oe2403sp3.x86_64.rpm",
          "util-linux-2.39.1-38.oe2403sp3.x86_64.rpm",
          "util-linux-debuginfo-2.39.1-38.oe2403sp3.x86_64.rpm",
          "util-linux-debugsource-2.39.1-38.oe2403sp3.x86_64.rpm",
          "util-linux-devel-2.39.1-38.oe2403sp3.x86_64.rpm",
          "util-linux-user-2.39.1-38.oe2403sp3.x86_64.rpm",
          "uuidd-2.39.1-38.oe2403sp3.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP3",
        "name": "util-linux",
        "purl": "pkg:rpm/openEuler/util-linux\u0026distro=openEuler-24.03-LTS-SP3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.39.1-38.oe2403sp3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "Medium"
  },
  "details": "The util-linux package contains a random collection of files that implements some low-level basic linux utilities.\r\n\r\nSecurity Fix(es):\n\nutil-linux is a random collection of Linux utilities. Prior to version 2.41.4, a TOCTOU (Time-of-Check-Time-of-Use) vulnerability has been identified in the SUID binary /usr/bin/mount from util-linux. The mount binary, when setting up loop devices, validates the source file path with user privileges via fork() + setuid() + realpath(), but subsequently re-canonicalizes and opens it with root privileges (euid=0) without verifying that the path has not been replaced between both operations. Neither O_NOFOLLOW, nor inode comparison, nor post-open fstat() are employed. This allows a local unprivileged user to replace the source file with a symlink pointing to any root-owned file or device during the race window, causing the SUID binary to open and mount it as root. Exploitation requires an /etc/fstab entry with user,loop options whose path points to a directory where the attacker has write permission, and that /usr/bin/mount has the SUID bit set (the default configuration on virtually all Linux distributions). The impact is unauthorized read access to root-protected files and block devices, including backup images, disk volumes, and any file containing a valid filesystem. This issue has been patched in version 2.41.4.(CVE-2026-27456)",
  "id": "OESA-2026-2211",
  "modified": "2026-08-06T11:11:11Z",
  "published": "2026-05-09T11:11:11Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-2211"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-27456"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "util-linux security update",
  "upstream": [
    "CVE-2026-27456"
  ]
}

CVE-2026-27456 (GCVE-0-2026-27456)

Vulnerability from cvelistv5 – Published: 2026-04-03 21:23 – Updated: 2026-04-06 15:42

Title

util-linux: TOCTOU Race Condition in util-linux mount(8) - Loop Device Setup

Summary

Severity

4.7 (Medium)


                        
                          CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-06 15:38 UTC

CWE

CWE-59 - Improper Link Resolution Before File Access ('Link Following')
CWE-269 - Improper Privilege Management
CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition

Assigner

GitHub_M mitre root

References

3 references

URL	Tags
https://github.com/util-linux/util-linux/security…	x_refsource_CONFIRM
https://github.com/util-linux/util-linux/commit/5…	x_refsource_MISC
https://github.com/util-linux/util-linux/releases…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
util-linux	util-linux	Affected: < 2.41.4

Show details on NVD website

JSON

To clipboard

{
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    "adp": [
      {
        "metrics": [
          {
            "other": {
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                "id": "CVE-2026-27456",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-06T15:38:42.794607Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-06T15:42:35.774Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/util-linux/util-linux/security/advisories/GHSA-qq4x-vfq4-9h9g"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "util-linux",
          "vendor": "util-linux",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 2.41.4"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "util-linux is a random collection of Linux utilities. Prior to version 2.41.4, a TOCTOU (Time-of-Check-Time-of-Use) vulnerability has been identified in the SUID binary /usr/bin/mount from util-linux. The mount binary, when setting up loop devices, validates the source file path with user privileges via fork() + setuid() + realpath(), but subsequently re-canonicalizes and opens it with root privileges (euid=0) without verifying that the path has not been replaced between both operations. Neither O_NOFOLLOW, nor inode comparison, nor post-open fstat() are employed. This allows a local unprivileged user to replace the source file with a symlink pointing to any root-owned file or device during the race window, causing the SUID binary to open and mount it as root. Exploitation requires an /etc/fstab entry with user,loop options whose path points to a directory where the attacker has write permission, and that /usr/bin/mount has the SUID bit set (the default configuration on virtually all Linux distributions). The impact is unauthorized read access to root-protected files and block devices, including backup images, disk volumes, and any file containing a valid filesystem. This issue has been patched in version 2.41.4."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "NONE",
            "baseScore": 4.7,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-59",
              "description": "CWE-59: Improper Link Resolution Before File Access (\u0027Link Following\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-269",
              "description": "CWE-269: Improper Privilege Management",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-367",
              "description": "CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-03T21:23:00.984Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/util-linux/util-linux/security/advisories/GHSA-qq4x-vfq4-9h9g",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/util-linux/util-linux/security/advisories/GHSA-qq4x-vfq4-9h9g"
        },
        {
          "name": "https://github.com/util-linux/util-linux/commit/5e390467b26a3cf3fecc04e1a0d482dff3162fc4",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/util-linux/util-linux/commit/5e390467b26a3cf3fecc04e1a0d482dff3162fc4"
        },
        {
          "name": "https://github.com/util-linux/util-linux/releases/tag/v2.41.4",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/util-linux/util-linux/releases/tag/v2.41.4"
        }
      ],
      "source": {
        "advisory": "GHSA-qq4x-vfq4-9h9g",
        "discovery": "UNKNOWN"
      },
      "title": "util-linux: TOCTOU Race Condition in util-linux mount(8) - Loop Device Setup"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-27456",
    "datePublished": "2026-04-03T21:23:00.984Z",
    "dateReserved": "2026-02-19T17:25:31.100Z",
    "dateUpdated": "2026-04-06T15:42:35.774Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

OESA-2026-2211 (CVE-2026-27456)

CVE-2026-27456 (GCVE-0-2026-27456)

Tags

Sightings

Nomenclature

Related by attack behaviour