Vulnerability-Lookup

GHSA-C42X-XW5M-9J9P

Vulnerability from github – Published: 2025-05-20 18:30 – Updated: 2025-11-03 21:33

Details

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

ksmbd: prevent out-of-bounds stream writes by validating *pos

ksmbd_vfs_stream_write() did not validate whether the write offset (pos) was within the bounds of the existing stream data length (v_len). If pos was greater than or equal to v_len, this could lead to an out-of-bounds memory write.

This patch adds a check to ensure *pos is less than v_len before proceeding. If the condition fails, -EINVAL is returned.

Severity

7.8 (High)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2025-37947"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-787"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-05-20T16:15:32Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: prevent out-of-bounds stream writes by validating *pos\n\nksmbd_vfs_stream_write() did not validate whether the write offset\n(*pos) was within the bounds of the existing stream data length (v_len).\nIf *pos was greater than or equal to v_len, this could lead to an\nout-of-bounds memory write.\n\nThis patch adds a check to ensure *pos is less than v_len before\nproceeding. If the condition fails, -EINVAL is returned.",
  "id": "GHSA-c42x-xw5m-9j9p",
  "modified": "2025-11-03T21:33:55Z",
  "published": "2025-05-20T18:30:56Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-37947"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/04c8a38c60346bb5a7c49b276de7233f703ce9cb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0ca6df4f40cf4c32487944aaf48319cb6c25accc"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7f61da79df86fd140c7768e668ad846bfa7ec8e1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d62ba16563a86aae052f96d270b3b6f78fca154c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e6356499fd216ed6343ae0363f4c9303f02c5034"
    },
    {
      "type": "WEB",
      "url": "https://github.com/doyensec/KSMBD-CVE-2025-37947/blob/main/CVE-2025-37947.c"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2025/08/msg00010.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2025-37947 (GCVE-0-2025-37947)

Vulnerability from cvelistv5 – Published: 2025-05-20 16:01 – Updated: 2026-08-05 11:58

Title

ksmbd: prevent out-of-bounds stream writes by validating *pos

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: prevent out-of-bounds stream writes by validating *pos ksmbd_vfs_stream_write() did not validate whether the write offset (*pos) was within the bounds of the existing stream data length (v_len). If *pos was greater than or equal to v_len, this could lead to an out-of-bounds memory write. This patch adds a check to ensure *pos is less than v_len before proceeding. If the condition fails, -EINVAL is returned.

Severity

8.8 (High)


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

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 2025-10-10 03:55 UTC

CWE

CWE-787 - Out-of-bounds Write

Assigner

Linux mitre root

References

7 references

URL	Tags
https://git.kernel.org/stable/c/7f61da79df86fd140…
https://git.kernel.org/stable/c/04c8a38c60346bb5a…
https://git.kernel.org/stable/c/d62ba16563a86aae0…
https://git.kernel.org/stable/c/e6356499fd216ed63…
https://git.kernel.org/stable/c/0ca6df4f40cf4c324…
https://github.com/doyensec/KSMBD-CVE-2025-37947/…	exploit
https://lists.debian.org/debian-lts-announce/2025…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 7f61da79df86fd140c7768e668ad846bfa7ec8e1 (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 04c8a38c60346bb5a7c49b276de7233f703ce9cb (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < d62ba16563a86aae052f96d270b3b6f78fca154c (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < e6356499fd216ed6343ae0363f4c9303f02c5034 (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 0ca6df4f40cf4c32487944aaf48319cb6c25accc (git)
Linux	Linux	Affected: 5.15 Unaffected: 0 , < 5.15 (semver) Unaffected: 6.1.139 , ≤ 6.1.* (semver) Unaffected: 6.6.91 , ≤ 6.6.* (semver) Unaffected: 6.12.29 , ≤ 6.12.* (semver) Unaffected: 6.14.7 , ≤ 6.14.* (semver) Unaffected: 6.15 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "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"
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            }
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            },
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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.

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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GHSA-C42X-XW5M-9J9P

CVE-2025-37947 (GCVE-0-2025-37947)

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