Vulnerability-Lookup

GHSA-3RCG-456G-86P6

Vulnerability from github – Published: 2025-05-20 18:30 – Updated: 2025-12-07 00:30

Details

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

ksmbd: fix use-after-free in session logoff

The sess->user object can currently be in use by another thread, for example if another connection has sent a session setup request to bind to the session being free'd. The handler for that connection could be in the smb2_sess_setup function which makes use of sess->user.

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-2025-37899"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-05-20T16:15:26Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix use-after-free in session logoff\n\nThe sess-\u003euser object can currently be in use by another thread, for\nexample if another connection has sent a session setup request to\nbind to the session being free\u0027d. The handler for that connection could\nbe in the smb2_sess_setup function which makes use of sess-\u003euser.",
  "id": "GHSA-3rcg-456g-86p6",
  "modified": "2025-12-07T00:30:55Z",
  "published": "2025-05-20T18:30:54Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-37899"
    },
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      "url": "https://git.kernel.org/stable/c/02d16046cd11a5c037b28c12ffb818c56dd3ef43"
    },
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      "url": "https://git.kernel.org/stable/c/2fc9feff45d92a92cd5f96487655d5be23fb7e2b"
    },
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      "url": "https://git.kernel.org/stable/c/70ad6455139e26e85f48f95d0e21f351c1909342"
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    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/931dc8a3670f71c45c0b1379ea4e92dafbda1aca"
    },
    {
      "type": "WEB",
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    },
    {
      "type": "WEB",
      "url": "https://news.ycombinator.com/item?id=44081338"
    },
    {
      "type": "WEB",
      "url": "https://sean.heelan.io/2025/05/22/how-i-used-o3-to-find-cve-2025-37899-a-remote-zeroday-vulnerability-in-the-linux-kernels-smb-implementation"
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      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2025-37899 (GCVE-0-2025-37899)

Vulnerability from cvelistv5 – Published: 2025-05-20 15:21 – Updated: 2026-08-05 11:58

Title

ksmbd: fix use-after-free in session logoff

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in session logoff The sess->user object can currently be in use by another thread, for example if another connection has sent a session setup request to bind to the session being free'd. The handler for that connection could be in the smb2_sess_setup function which makes use of sess->user.

Severity

8.8 (High)


                        
                          CVSS:3.1/AV:N/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/931dc8a3670f71c45…
https://git.kernel.org/stable/c/70ad6455139e26e85…
https://git.kernel.org/stable/c/d5ec1d79509b3ee01…
https://git.kernel.org/stable/c/02d16046cd11a5c03…
https://git.kernel.org/stable/c/2fc9feff45d92a92c…
https://sean.heelan.io/2025/05/22/how-i-used-o3-t…
https://news.ycombinator.com/item?id=44081338

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 931dc8a3670f71c45c0b1379ea4e92dafbda1aca (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 70ad6455139e26e85f48f95d0e21f351c1909342 (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < d5ec1d79509b3ee01de02c236f096bc050221b7f (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 02d16046cd11a5c037b28c12ffb818c56dd3ef43 (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 2fc9feff45d92a92cd5f96487655d5be23fb7e2b (git)
Linux	Linux	Affected: 5.15 Unaffected: 0 , < 5.15 (semver) Unaffected: 6.1.159 , ≤ 6.1.* (semver) Unaffected: 6.6.119 , ≤ 6.6.* (semver) Unaffected: 6.12.28 , ≤ 6.12.* (semver) Unaffected: 6.14.6 , ≤ 6.14.* (semver) Unaffected: 6.15 , ≤ * (original_commit_for_fix)

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          "dateUpdated": "2025-05-24T19:05:08.356Z",
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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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