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CVE-2025-37777 (GCVE-0-2025-37777)

Vulnerability from cvelistv5 – Published: 2025-05-01 13:07 – Updated: 2026-08-05 11:57
VLAI
Title
ksmbd: fix use-after-free in __smb2_lease_break_noti()
Summary
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in __smb2_lease_break_noti() Move tcp_transport free to ksmbd_conn_free. If ksmbd connection is referenced when ksmbd server thread terminates, It will not be freed, but conn->tcp_transport is freed. __smb2_lease_break_noti can be performed asynchronously when the connection is disconnected. __smb2_lease_break_noti calls ksmbd_conn_write, which can cause use-after-free when conn->ksmbd_transport is already freed.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 1da8bd9a10ecd718692732294d15fd801c0eabb5 (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 1aec4d14cf81b7b3e7b69eb1cfa94144eed7138e (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < e59796fc80603bcd8569d4d2e10b213c1918edb4 (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 21a4e47578d44c6b37c4fc4aba8ed7cc8dbb13de (git)
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Linux Linux Affected: 5.15
Unaffected: 0 , < 5.15 (semver)
Unaffected: 6.6.101 , ≤ 6.6.* (semver)
Unaffected: 6.12.26 , ≤ 6.12.* (semver)
Unaffected: 6.14.4 , ≤ 6.14.* (semver)
Unaffected: 6.15 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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          },
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    "redhat_vex": {
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      "current_release_date": "2026-06-30T10:28:57+00:00",
      "cve": "CVE-2025-37777",
      "id": "CVE-2025-37777",
      "initial_release_date": "2025-05-01T00:00:00+00:00",
      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: ksmbd: fix use-after-free in __smb2_lease_break_noti()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-37777.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-08-31T00:21:29Z",
      "cve": "CVE-2025-37777",
      "id": "CVE-2025-37777",
      "initial_release_date": "2025-05-02T02:02:32Z",
      "product_status:known_not_affected": "564",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2025-37777",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2025-37777.json",
      "version": "13"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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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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