Vulnerability-Lookup

GHSA-2QHG-8P2V-WF99

Vulnerability from github – Published: 2026-05-27 15:33 – Updated: 2026-06-24 18:32

Details

In the Linux kernel, the following vulnerability has been resolved:

fat: avoid parent link count underflow in rmdir

Corrupted FAT images can leave a directory inode with an incorrect i_nlink (e.g. 2 even though subdirectories exist). rmdir then unconditionally calls drop_nlink(dir) and can drive i_nlink to 0, triggering the WARN_ON in drop_nlink().

Add a sanity check in vfat_rmdir() and msdos_rmdir(): only drop the parent link count when it is at least 3, otherwise report a filesystem error.

Severity

5.5 (Medium)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-45915"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-27T14:17:06Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nfat: avoid parent link count underflow in rmdir\n\nCorrupted FAT images can leave a directory inode with an incorrect\ni_nlink (e.g. 2 even though subdirectories exist). rmdir then\nunconditionally calls drop_nlink(dir) and can drive i_nlink to 0,\ntriggering the WARN_ON in drop_nlink().\n\nAdd a sanity check in vfat_rmdir() and msdos_rmdir(): only drop the\nparent link count when it is at least 3, otherwise report a filesystem\nerror.",
  "id": "GHSA-2qhg-8p2v-wf99",
  "modified": "2026-06-24T18:32:28Z",
  "published": "2026-05-27T15:33:16Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-45915"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/17866f8a0822d414cb02e621cf003a7d04396ef8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7fe0de287e931e07cb96ecf1f449b2ebdb0e1115"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8cafcb881364af5ef3a8b9fed4db254054033d8a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/955c5d670b5ae07c78f4345e23a895638db96ce1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9894c79fd9466612d0514be157b5c30cd93aa645"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/cd569b87378b9c33ae13c23d6bb9d205d66f7c4b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d0bb592fa9def2bace90ac8926c0a1d6fa8c1aa0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d3b7ffa90f613938128432c7b2f35b7aa4bdd86b"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-45915 (GCVE-0-2026-45915)

Vulnerability from cvelistv5 – Published: 2026-05-27 12:17 – Updated: 2026-05-27 12:17

Title

fat: avoid parent link count underflow in rmdir

Summary

In the Linux kernel, the following vulnerability has been resolved: fat: avoid parent link count underflow in rmdir Corrupted FAT images can leave a directory inode with an incorrect i_nlink (e.g. 2 even though subdirectories exist). rmdir then unconditionally calls drop_nlink(dir) and can drive i_nlink to 0, triggering the WARN_ON in drop_nlink(). Add a sanity check in vfat_rmdir() and msdos_rmdir(): only drop the parent link count when it is at least 3, otherwise report a filesystem error.

Severity

No CVSS data available.

Assigner

Linux mitre root

References

8 references

URL	Tags
https://git.kernel.org/stable/c/7fe0de287e931e07c…
https://git.kernel.org/stable/c/9894c79fd9466612d…
https://git.kernel.org/stable/c/cd569b87378b9c33a…
https://git.kernel.org/stable/c/d3b7ffa90f6139381…
https://git.kernel.org/stable/c/955c5d670b5ae07c7…
https://git.kernel.org/stable/c/17866f8a0822d414c…
https://git.kernel.org/stable/c/d0bb592fa9def2bac…
https://git.kernel.org/stable/c/8cafcb881364af5ef…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 9a53c3a783c2fa9b969628e65695c11c3e51e673 , < 7fe0de287e931e07cb96ecf1f449b2ebdb0e1115 (git) Affected: 9a53c3a783c2fa9b969628e65695c11c3e51e673 , < 9894c79fd9466612d0514be157b5c30cd93aa645 (git) Affected: 9a53c3a783c2fa9b969628e65695c11c3e51e673 , < cd569b87378b9c33ae13c23d6bb9d205d66f7c4b (git) Affected: 9a53c3a783c2fa9b969628e65695c11c3e51e673 , < d3b7ffa90f613938128432c7b2f35b7aa4bdd86b (git) Affected: 9a53c3a783c2fa9b969628e65695c11c3e51e673 , < 955c5d670b5ae07c78f4345e23a895638db96ce1 (git) Affected: 9a53c3a783c2fa9b969628e65695c11c3e51e673 , < 17866f8a0822d414cb02e621cf003a7d04396ef8 (git) Affected: 9a53c3a783c2fa9b969628e65695c11c3e51e673 , < d0bb592fa9def2bace90ac8926c0a1d6fa8c1aa0 (git) Affected: 9a53c3a783c2fa9b969628e65695c11c3e51e673 , < 8cafcb881364af5ef3a8b9fed4db254054033d8a (git)
Linux	Linux	Affected: 2.6.19 Unaffected: 0 , < 2.6.19 (semver) Unaffected: 5.10.252 , ≤ 5.10.* (semver) Unaffected: 5.15.202 , ≤ 5.15.* (semver) Unaffected: 6.1.165 , ≤ 6.1.* (semver) Unaffected: 6.6.128 , ≤ 6.6.* (semver) Unaffected: 6.12.75 , ≤ 6.12.* (semver) Unaffected: 6.18.14 , ≤ 6.18.* (semver) Unaffected: 6.19.4 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

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{
  "containers": {
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        {
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          "programFiles": [
            "fs/fat/namei_msdos.c",
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          "versions": [
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          "vendor": "Linux",
          "versions": [
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              "version": "2.6.19"
            },
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              "lessThan": "2.6.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
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            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.202",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.165",
              "versionType": "semver"
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            {
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              "status": "unaffected",
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              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.75",
              "versionType": "semver"
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              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.14",
              "versionType": "semver"
            },
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              "status": "unaffected",
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          "url": "https://git.kernel.org/stable/c/8cafcb881364af5ef3a8b9fed4db254054033d8a"
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      "title": "fat: avoid parent link count underflow in rmdir",
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}

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.

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