CVE-2023-4515 (GCVE-0-2023-4515)

Vulnerability from cvelistv5 – Published: 2025-08-16 13:25 – Updated: 2026-08-05 09:09
VLAI
Title
ksmbd: validate command request size
Summary
In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate command request size In commit 2b9b8f3b68ed ("ksmbd: validate command payload size"), except for SMB2_OPLOCK_BREAK_HE command, the request size of other commands is not checked, it's not expected. Fix it by add check for request size of other commands.
Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 35f450f54dca1519bb24faacd0428db09f89a11f , < 595679098bdcdbfbba91ebe07a2f7f208df93870 (git)
Affected: 9650cf70ec9d94ff34daa088b643229231723c26 , < c6bef3bc30fd4a175aef846b7d928a6c40d091cd (git)
Affected: 2b9b8f3b68edb3d67d79962f02e26dbb5ae3808d , < ff7236b66d69582f90cf5616e63cfc3dc18142bb (git)
Affected: 2b9b8f3b68edb3d67d79962f02e26dbb5ae3808d , < 5aa4fda5aa9c2a5a7bac67b4a12b089ab81fee3c (git)
Affected: 768caf4019f0391c0b6452afe34cea1704133f7b (git)
Affected: 5.15.121 , < 5.15.127 (semver)
Affected: 6.1.36 , < 6.1.46 (semver)
Affected: 6.3.10 , < 6.4 (semver)
Create a notification for this product.
Linux Linux Affected: 6.4
Unaffected: 0 , < 6.4 (semver)
Unaffected: 5.15.127 , ≤ 5.15.* (semver)
Unaffected: 6.1.46 , ≤ 6.1.* (semver)
Unaffected: 6.4.11 , ≤ 6.4.* (semver)
Unaffected: 6.5 , ≤ * (original_commit_for_fix)
Create a notification for this product.
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    "redhat_vex": {
      "aggregate_severity": "None",
      "current_release_date": "2026-06-30T10:22:34+00:00",
      "cve": "CVE-2023-4515",
      "id": "CVE-2023-4515",
      "initial_release_date": "2023-01-01T00:00:00+00:00",
      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: ksmbd: validate command request size",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2023/cve-2023-4515.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-08-05T01:08:21Z",
      "cve": "CVE-2023-4515",
      "id": "CVE-2023-4515",
      "initial_release_date": "2025-08-16T23:25:31Z",
      "product_status:known_affected": "394",
      "product_status:known_not_affected": "337",
      "product_status:recommended": "354",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2023-4515",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2023-4515.json",
      "version": "49"
    }
  }
}



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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.

Sightings

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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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