Vulnerability-Lookup

GHSA-F39X-MP5J-46F3

Vulnerability from github – Published: 2025-07-04 15:31 – Updated: 2025-12-18 18:30

Details

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

ksmbd: fix null pointer dereference in destroy_previous_session

If client set ->PreviousSessionId on kerberos session setup stage, NULL pointer dereference error will happen. Since sess->user is not set yet, It can pass the user argument as NULL to destroy_previous_session. sess->user will be set in ksmbd_krb5_authenticate(). So this patch move calling destroy_previous_session() after ksmbd_krb5_authenticate().

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-2025-38191"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-07-04T14:15:26Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix null pointer dereference in destroy_previous_session\n\nIf client set -\u003ePreviousSessionId on kerberos session setup stage,\nNULL pointer dereference error will happen. Since sess-\u003euser is not\nset yet, It can pass the user argument as NULL to destroy_previous_session.\nsess-\u003euser will be set in ksmbd_krb5_authenticate(). So this patch move\ncalling destroy_previous_session() after ksmbd_krb5_authenticate().",
  "id": "GHSA-f39x-mp5j-46f3",
  "modified": "2025-12-18T18:30:28Z",
  "published": "2025-07-04T15:31:08Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-38191"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/076f1adefb9837977af7ed233883842ddc446644"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0902625a24eea7fdc187faa5d97df244d159dd6e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1193486dffb7432a09f57f5d09049b4d4123538b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/281afc52e2961cd5dd8326ebc9c5bc40904c0468"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7ac5b66acafcc9292fb935d7e03790f2b8b2dc0e"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"
    },
    {
      "type": "WEB",
      "url": "https://www.zerodayinitiative.com/advisories/ZDI-25-610"
    }
  ],
  "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-2025-38191 (GCVE-0-2025-38191)

Vulnerability from cvelistv5 – Published: 2025-07-04 13:37 – Updated: 2026-08-05 12:00

Title

ksmbd: fix null pointer dereference in destroy_previous_session

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix null pointer dereference in destroy_previous_session If client set ->PreviousSessionId on kerberos session setup stage, NULL pointer dereference error will happen. Since sess->user is not set yet, It can pass the user argument as NULL to destroy_previous_session. sess->user will be set in ksmbd_krb5_authenticate(). So this patch move calling destroy_previous_session() after ksmbd_krb5_authenticate().

Severity

7.5 (High)


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

Assigner

Linux mitre root Scorecard

References

7 references

URL	Tags
https://git.kernel.org/stable/c/281afc52e2961cd5d…
https://git.kernel.org/stable/c/0902625a24eea7fdc…
https://git.kernel.org/stable/c/1193486dffb7432a0…
https://git.kernel.org/stable/c/076f1adefb9837977…
https://git.kernel.org/stable/c/7ac5b66acafcc9292…
https://www.zerodayinitiative.com/advisories/ZDI-…
https://lists.debian.org/debian-lts-announce/2025…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 281afc52e2961cd5dd8326ebc9c5bc40904c0468 (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 0902625a24eea7fdc187faa5d97df244d159dd6e (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 1193486dffb7432a09f57f5d09049b4d4123538b (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 076f1adefb9837977af7ed233883842ddc446644 (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 7ac5b66acafcc9292fb935d7e03790f2b8b2dc0e (git)
Linux	Linux	Affected: 5.15 Unaffected: 0 , < 5.15 (semver) Unaffected: 6.1.142 , ≤ 6.1.* (semver) Unaffected: 6.6.95 , ≤ 6.6.* (semver) Unaffected: 6.12.35 , ≤ 6.12.* (semver) Unaffected: 6.15.4 , ≤ 6.15.* (semver) Unaffected: 6.16 , ≤ * (original_commit_for_fix)

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JSON

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        "providerMetadata": {
          "dateUpdated": "2025-11-03T17:35:15.212Z",
          "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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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix null pointer dereference in destroy_previous_session\n\nIf client set -\u003ePreviousSessionId on kerberos session setup stage,\nNULL pointer dereference error will happen. Since sess-\u003euser is not\nset yet, It can pass the user argument as NULL to destroy_previous_session.\nsess-\u003euser will be set in ksmbd_krb5_authenticate(). So this patch move\ncalling destroy_previous_session() after ksmbd_krb5_authenticate()."
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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.

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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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GHSA-F39X-MP5J-46F3

CVE-2025-38191 (GCVE-0-2025-38191)

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