Vulnerability-Lookup

GHSA-9CP7-M95W-Q87H

Vulnerability from github – Published: 2025-11-12 12:30 – Updated: 2026-09-02 15:33

Details

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

smc: Use __sk_dst_get() and dst_dev_rcu() in smc_clc_prfx_match().

smc_clc_prfx_match() is called from smc_listen_work() and not under RCU nor RTNL.

Using sk_dst_get(sk)->dev could trigger UAF.

Let's use __sk_dst_get() and dst_dev_rcu().

Note that the returned value of smc_clc_prfx_match() is not used in the caller.

Severity

8.1 (High)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2025-40168"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-11-12T11:15:47Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmc: Use __sk_dst_get() and dst_dev_rcu() in smc_clc_prfx_match().\n\nsmc_clc_prfx_match() is called from smc_listen_work() and\nnot under RCU nor RTNL.\n\nUsing sk_dst_get(sk)-\u003edev could trigger UAF.\n\nLet\u0027s use __sk_dst_get() and dst_dev_rcu().\n\nNote that the returned value of smc_clc_prfx_match() is not\nused in the caller.",
  "id": "GHSA-9cp7-m95w-q87h",
  "modified": "2026-09-02T15:33:18Z",
  "published": "2025-11-12T12:30:28Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-40168"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/235f81045c008169cc4e1955b4a64e118eebe61b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/326e5cf301d0bec0a672aa834d8254c4f9df6255"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3f119c37aa293af41400cccb3d89fab8dcf774b0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4f5f52a5842937f945582a93cb9daed9ea526fee"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d26e80f7fb62d77757b67a1b94e4ac756bc9c658"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2025-40168 (GCVE-0-2025-40168)

Vulnerability from cvelistv5 – Published: 2025-11-12 10:46 – Updated: 2026-09-02 12:49

Title

smc: Use __sk_dst_get() and dst_dev_rcu() in smc_clc_prfx_match().

Summary

In the Linux kernel, the following vulnerability has been resolved: smc: Use __sk_dst_get() and dst_dev_rcu() in smc_clc_prfx_match(). smc_clc_prfx_match() is called from smc_listen_work() and not under RCU nor RTNL. Using sk_dst_get(sk)->dev could trigger UAF. Let's use __sk_dst_get() and dst_dev_rcu(). Note that the returned value of smc_clc_prfx_match() is not used in the caller.

Severity

8.1 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-16 19:59 UTC

Assigner

Linux mitre root

References

5 references

URL	Tags
https://git.kernel.org/stable/c/3f119c37aa293af41…
https://git.kernel.org/stable/c/4f5f52a5842937f94…
https://git.kernel.org/stable/c/326e5cf301d0bec0a…
https://git.kernel.org/stable/c/d26e80f7fb62d7775…
https://git.kernel.org/stable/c/235f81045c008169c…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: a046d57da19f812216f393e7c535f5858f793ac3 , < 3f119c37aa293af41400cccb3d89fab8dcf774b0 (git) Affected: a046d57da19f812216f393e7c535f5858f793ac3 , < 4f5f52a5842937f945582a93cb9daed9ea526fee (git) Affected: a046d57da19f812216f393e7c535f5858f793ac3 , < 326e5cf301d0bec0a672aa834d8254c4f9df6255 (git) Affected: a046d57da19f812216f393e7c535f5858f793ac3 , < d26e80f7fb62d77757b67a1b94e4ac756bc9c658 (git) Affected: a046d57da19f812216f393e7c535f5858f793ac3 , < 235f81045c008169cc4e1955b4a64e118eebe61b (git)
Linux	Linux	Affected: 4.11 Unaffected: 0 , < 4.11 (semver) Unaffected: 6.1.187 , ≤ 6.1.* (semver) Unaffected: 6.6.156 , ≤ 6.6.* (semver) Unaffected: 6.12.108 , ≤ 6.12.* (semver) Unaffected: 6.17.3 , ≤ 6.17.* (semver) Unaffected: 6.18 , ≤ * (original_commit_for_fix)

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                "id": "CVE-2025-40168",
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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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