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CVE-2023-52440 (GCVE-0-2023-52440)

Vulnerability from cvelistv5 – Published: 2024-02-21 07:21 – Updated: 2026-08-15 12:23
VLAI
Title
ksmbd: fix slub overflow in ksmbd_decode_ntlmssp_auth_blob()
Summary
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix slub overflow in ksmbd_decode_ntlmssp_auth_blob() If authblob->SessionKey.Length is bigger than session key size(CIFS_KEY_SIZE), slub overflow can happen in key exchange codes. cifs_arc4_crypt copy to session key array from SessionKey from client.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/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 2024-09-10 16:02 UTC
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: c5049d2d73b2dc8e6bb64be633250bad1ae3d9ef , < bd554ed4fdc3d38404a1c43d428432577573e809 (git)
Affected: f9929ef6a2a55f03aac61248c6a3a987b8546f2a , < 30fd6521b2fbd9b767e438e31945e5ea3e3a2fba (git)
Affected: f9929ef6a2a55f03aac61248c6a3a987b8546f2a , < 7f1d6cb0eb6af3a8088dc24b7ddee9a9711538c4 (git)
Affected: f9929ef6a2a55f03aac61248c6a3a987b8546f2a , < ecd7e1c562cb08e41957fcd4b0e404de5ab38e20 (git)
Affected: f9929ef6a2a55f03aac61248c6a3a987b8546f2a , < 4b081ce0d830b684fdf967abc3696d1261387254 (git)
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Linux Linux Affected: 5.17
Unaffected: 0 , < 5.17 (semver)
Unaffected: 6.1.52 , ≤ 6.1.* (semver)
Unaffected: 6.4.15 , ≤ 6.4.* (semver)
Unaffected: 6.5.2 , ≤ 6.5.* (semver)
Unaffected: 6.6 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "ksmbd: fix slub overflow in ksmbd_decode_ntlmssp_auth_blob()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2023/cve-2023-52440.json",
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      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2023-52440.json",
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}



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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

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.


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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.