Vulnerability-Lookup

OESA-2026-3723 (CVE-2026-76642)

Vulnerability from osv_openeuler – Published: 2026-09-14 16:33 – Updated: 2026-09-14 16:33 – 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 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.(CVE-2026-76642)

Severity

7.8 (High)


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

References

URL

Type

	https://www.openeuler.org/zh/security/security-bu…	ADVISORY
	https://nvd.nist.gov/vuln/detail/CVE-2026-76642	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "libblkid-2.39.1-41.oe2403sp4.aarch64.rpm",
          "libfdisk-2.39.1-41.oe2403sp4.aarch64.rpm",
          "libmount-2.39.1-41.oe2403sp4.aarch64.rpm",
          "libsmartcols-2.39.1-41.oe2403sp4.aarch64.rpm",
          "libuuid-2.39.1-41.oe2403sp4.aarch64.rpm",
          "python3-libmount-2.39.1-41.oe2403sp4.aarch64.rpm",
          "util-linux-2.39.1-41.oe2403sp4.aarch64.rpm",
          "util-linux-debuginfo-2.39.1-41.oe2403sp4.aarch64.rpm",
          "util-linux-debugsource-2.39.1-41.oe2403sp4.aarch64.rpm",
          "util-linux-devel-2.39.1-41.oe2403sp4.aarch64.rpm",
          "util-linux-user-2.39.1-41.oe2403sp4.aarch64.rpm",
          "uuidd-2.39.1-41.oe2403sp4.aarch64.rpm"
        ],
        "noarch": [
          "util-linux-help-2.39.1-41.oe2403sp4.noarch.rpm"
        ],
        "src": [
          "util-linux-2.39.1-41.oe2403sp4.src.rpm"
        ],
        "x86_64": [
          "libblkid-2.39.1-41.oe2403sp4.x86_64.rpm",
          "libfdisk-2.39.1-41.oe2403sp4.x86_64.rpm",
          "libmount-2.39.1-41.oe2403sp4.x86_64.rpm",
          "libsmartcols-2.39.1-41.oe2403sp4.x86_64.rpm",
          "libuuid-2.39.1-41.oe2403sp4.x86_64.rpm",
          "python3-libmount-2.39.1-41.oe2403sp4.x86_64.rpm",
          "util-linux-2.39.1-41.oe2403sp4.x86_64.rpm",
          "util-linux-debuginfo-2.39.1-41.oe2403sp4.x86_64.rpm",
          "util-linux-debugsource-2.39.1-41.oe2403sp4.x86_64.rpm",
          "util-linux-devel-2.39.1-41.oe2403sp4.x86_64.rpm",
          "util-linux-user-2.39.1-41.oe2403sp4.x86_64.rpm",
          "uuidd-2.39.1-41.oe2403sp4.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP4",
        "name": "util-linux",
        "purl": "pkg:rpm/openEuler/util-linux\u0026distro=openEuler-24.03-LTS-SP4"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.39.1-41.oe2403sp4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "High"
  },
  "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 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.(CVE-2026-76642)",
  "id": "OESA-2026-3723",
  "modified": "2026-09-14T16:33:45Z",
  "published": "2026-09-14T16:33:45Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-3723"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-76642"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "util-linux security update",
  "upstream": [
    "CVE-2026-76642"
  ]
}

CVE-2026-76642 (GCVE-0-2026-76642)

Vulnerability from cvelistv5 – Published: 2026-09-03 10:54 – Updated: 2026-09-03 14:00

Title

util-linux libmount Privilege Escalation via Failed Mount Helper

Summary

Severity

8.5 (High)


                        
                          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

7.8 (High)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-03 14:00 UTC

CWE

CWE-390 - Detection of Error Condition Without Action

Assigner

VulnCheck mitre root

References

8 references

URL	Tags
https://github.com/util-linux/util-linux/security…	vendor-advisory
https://github.com/util-linux/util-linux/commit/f…	patch
https://github.com/util-linux/util-linux/commit/1…	patch
https://github.com/util-linux/util-linux/commit/a…	patch
https://github.com/util-linux/util-linux/blob/v2.…	technical-description
https://github.com/util-linux/util-linux/blob/v2.…	technical-description
https://github.com/util-linux/util-linux	product
https://www.vulncheck.com/advisories/util-linux-l…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
util-linux	util-linux	Affected: 2.39 , < 2.41.6 (custom) Affected: 2.42 , < 2.42.3 (custom) cpe:2.3:a:kernel:util-linux:::::::: cpe:2.3:a:kernel:util-linux::::::::

Date Public

2026-09-02 00:00

Credits

Andreas Gabriel Berbescu Ivan Redondo Plaza

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-76642",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-03T14:00:22.814411Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-03T14:00:29.374Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/util-linux/util-linux/security/advisories/GHSA-m25x-3hj9-m26f"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:github/util-linux/util-linux",
          "product": "util-linux",
          "vendor": "util-linux",
          "versions": [
            {
              "lessThan": "2.41.6",
              "status": "affected",
              "version": "2.39",
              "versionType": "custom"
            },
            {
              "lessThan": "2.42.3",
              "status": "affected",
              "version": "2.42",
              "versionType": "custom"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:kernel:util-linux:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "2.41.6",
                  "versionStartIncluding": "2.39",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:a:kernel:util-linux:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "2.42.3",
                  "versionStartIncluding": "2.42",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "Andreas Gabriel Berbescu"
        },
        {
          "lang": "en",
          "type": "reporter",
          "value": "Ivan Redondo Plaza"
        }
      ],
      "datePublic": "2026-09-02T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "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."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "LOCAL",
            "baseScore": 8.5,
            "baseSeverity": "HIGH",
            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "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",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          },
          "format": "CVSS"
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-390",
              "description": "Detection of Error Condition Without Action",
              "lang": "en",
              "type": "CWE"
            }
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      "providerMetadata": {
        "dateUpdated": "2026-09-03T10:54:08.150Z",
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          "url": "https://github.com/util-linux/util-linux/security/advisories/GHSA-m25x-3hj9-m26f"
        },
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          "url": "https://github.com/util-linux/util-linux/commit/f57cea130839c0af8dc0525274267ae4cfd66bbf"
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          "url": "https://github.com/util-linux/util-linux/blob/v2.42.2/libmount/src/context_mount.c#L476"
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          "url": "https://github.com/util-linux/util-linux/blob/v2.42.2/libmount/src/context_mount.c#L892"
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          "url": "https://github.com/util-linux/util-linux"
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          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/util-linux-libmount-privilege-escalation-via-failed-mount-helper"
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      "title": "util-linux libmount Privilege Escalation via Failed Mount Helper",
      "x_generator": {
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      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-76642",
    "datePublished": "2026-09-03T10:54:08.150Z",
    "dateReserved": "2026-08-19T14:53:58.575Z",
    "dateUpdated": "2026-09-03T14:00:29.374Z",
    "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.

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.
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Action not permitted

OESA-2026-3723 (CVE-2026-76642)

CVE-2026-76642 (GCVE-0-2026-76642)

Tags

Sightings

Nomenclature

Related by attack behaviour