Vulnerability-Lookup

GHSA-Q638-MXXH-QCHW

Vulnerability from github – Published: 2025-09-15 15:31 – Updated: 2026-05-12 15:31

Details

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

btrfs: abort transaction on unexpected eb generation at btrfs_copy_root()

If we find an unexpected generation for the extent buffer we are cloning at btrfs_copy_root(), we just WARN_ON() and don't error out and abort the transaction, meaning we allow to persist metadata with an unexpected generation. Instead of warning only, abort the transaction and return -EUCLEAN.

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-2025-39800"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-09-15T13:15:35Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: abort transaction on unexpected eb generation at btrfs_copy_root()\n\nIf we find an unexpected generation for the extent buffer we are cloning\nat btrfs_copy_root(), we just WARN_ON() and don\u0027t error out and abort the\ntransaction, meaning we allow to persist metadata with an unexpected\ngeneration. Instead of warning only, abort the transaction and return\n-EUCLEAN.",
  "id": "GHSA-q638-mxxh-qchw",
  "modified": "2026-05-12T15:31:08Z",
  "published": "2025-09-15T15:31:21Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-39800"
    },
    {
      "type": "WEB",
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-032379.html"
    },
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      "type": "WEB",
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    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4290e34fb87ae556b12c216efd0ae91583446b7a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4734255ef39b416864139dcda96a387fe5f33a6a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/da2124719f386b6e5d4d4b1a2e67c440e4d5892f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f4f5bd9251a4cbe55aaa05725c6c3c32ad1f74b3"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"
    }
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  "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-2025-39800 (GCVE-0-2025-39800)

Vulnerability from cvelistv5 – Published: 2025-09-15 12:36 – Updated: 2026-08-05 12:05

Title

btrfs: abort transaction on unexpected eb generation at btrfs_copy_root()

Summary

In the Linux kernel, the following vulnerability has been resolved: btrfs: abort transaction on unexpected eb generation at btrfs_copy_root() If we find an unexpected generation for the extent buffer we are cloning at btrfs_copy_root(), we just WARN_ON() and don't error out and abort the transaction, meaning we allow to persist metadata with an unexpected generation. Instead of warning only, abort the transaction and return -EUCLEAN.

Severity

7.8 (High)


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

Assigner

Linux mitre root

References

7 references

URL	Tags
https://git.kernel.org/stable/c/4290e34fb87ae556b…
https://git.kernel.org/stable/c/4734255ef39b41686…
https://git.kernel.org/stable/c/da2124719f386b6e5…
https://git.kernel.org/stable/c/f4f5bd9251a4cbe55…
https://git.kernel.org/stable/c/33e8f24b52d2796b8…
https://lists.debian.org/debian-lts-announce/2025…
https://cert-portal.siemens.com/productcert/html/…

Impacted products

3 products

Vendor	Product	Version
Linux	Linux	Affected: be20aa9dbadc8c06283784ee12bbc0d97dea3418 , < 4290e34fb87ae556b12c216efd0ae91583446b7a (git) Affected: be20aa9dbadc8c06283784ee12bbc0d97dea3418 , < 4734255ef39b416864139dcda96a387fe5f33a6a (git) Affected: be20aa9dbadc8c06283784ee12bbc0d97dea3418 , < da2124719f386b6e5d4d4b1a2e67c440e4d5892f (git) Affected: be20aa9dbadc8c06283784ee12bbc0d97dea3418 , < f4f5bd9251a4cbe55aaa05725c6c3c32ad1f74b3 (git) Affected: be20aa9dbadc8c06283784ee12bbc0d97dea3418 , < 33e8f24b52d2796b8cfb28c19a1a7dd6476323a8 (git)
Linux	Linux	Affected: 2.6.29 Unaffected: 0 , < 2.6.29 (semver) Unaffected: 6.1.149 , ≤ 6.1.* (semver) Unaffected: 6.6.103 , ≤ 6.6.* (semver) Unaffected: 6.12.44 , ≤ 6.12.* (semver) Unaffected: 6.16.4 , ≤ 6.16.* (semver) Unaffected: 6.17 , ≤ * (original_commit_for_fix)
Siemens	SIMATIC CN 4100	Affected: 0 , < V5.0 (custom)

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  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2025-11-03T17:43:30.834Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
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        "references": [
          {
            "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"
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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.

Related by attack behaviour

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