Vulnerability-Lookup

GHSA-45GW-FX24-H4PV

Vulnerability from github – Published: 2025-05-01 15:31 – Updated: 2026-04-18 09:30

Details

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

ksmbd: Fix dangling pointer in krb_authenticate

krb_authenticate frees sess->user and does not set the pointer to NULL. It calls ksmbd_krb5_authenticate to reinitialise sess->user but that function may return without doing so. If that happens then smb2_sess_setup, which calls krb_authenticate, will be accessing free'd memory when it later uses 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-2025-37778"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-05-01T14:15:41Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: Fix dangling pointer in krb_authenticate\n\nkrb_authenticate frees sess-\u003euser and does not set the pointer\nto NULL. It calls ksmbd_krb5_authenticate to reinitialise\nsess-\u003euser but that function may return without doing so. If\nthat happens then smb2_sess_setup, which calls krb_authenticate,\nwill be accessing free\u0027d memory when it later uses sess-\u003euser.",
  "id": "GHSA-45gw-fx24-h4pv",
  "modified": "2026-04-18T09:30:16Z",
  "published": "2025-05-01T15:31:44Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-37778"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1db2451de23e98bc864c6a6e52aa0d82c91cb325"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1e440d5b25b7efccb3defe542a73c51005799a5f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6e30c0e10210c714f3d4453dc258d4abcc70364e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b61f04d5d73c53d183019bafe22fb700a739bac5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d5b554bc8d554ed6ddf443d3db2fad9f665cec10"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e83e39a5f6a01a81411a4558a59a10f87aa88dd6"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00045.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-2025-37778 (GCVE-0-2025-37778)

Vulnerability from cvelistv5 – Published: 2025-05-01 13:07 – Updated: 2026-08-05 11:57

Title

ksmbd: Fix dangling pointer in krb_authenticate

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: Fix dangling pointer in krb_authenticate krb_authenticate frees sess->user and does not set the pointer to NULL. It calls ksmbd_krb5_authenticate to reinitialise sess->user but that function may return without doing so. If that happens then smb2_sess_setup, which calls krb_authenticate, will be accessing free'd memory when it later uses sess->user.

Severity

9.8 (Critical)


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

Assigner

Linux mitre root Scorecard

References

7 references

URL	Tags
https://git.kernel.org/stable/c/b61f04d5d73c53d18…
https://git.kernel.org/stable/c/d5b554bc8d554ed6d…
https://git.kernel.org/stable/c/1db2451de23e98bc8…
https://git.kernel.org/stable/c/6e30c0e10210c714f…
https://git.kernel.org/stable/c/e83e39a5f6a01a814…
https://git.kernel.org/stable/c/1e440d5b25b7efccb…
https://lists.debian.org/debian-lts-announce/2025…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < b61f04d5d73c53d183019bafe22fb700a739bac5 (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < d5b554bc8d554ed6ddf443d3db2fad9f665cec10 (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 1db2451de23e98bc864c6a6e52aa0d82c91cb325 (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 6e30c0e10210c714f3d4453dc258d4abcc70364e (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < e83e39a5f6a01a81411a4558a59a10f87aa88dd6 (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 1e440d5b25b7efccb3defe542a73c51005799a5f (git)
Linux	Linux	Affected: 5.15 Unaffected: 0 , < 5.15 (semver) Unaffected: 5.15.203 , ≤ 5.15.* (semver) Unaffected: 6.1.135 , ≤ 6.1.* (semver) Unaffected: 6.6.88 , ≤ 6.6.* (semver) Unaffected: 6.12.25 , ≤ 6.12.* (semver) Unaffected: 6.14.4 , ≤ 6.14.* (semver) Unaffected: 6.15 , ≤ * (original_commit_for_fix)

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JSON

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            "url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00045.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.

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.
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GHSA-45GW-FX24-H4PV

CVE-2025-37778 (GCVE-0-2025-37778)

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