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CVE-2026-64136 (GCVE-0-2026-64136)

Vulnerability from cvelistv5 – Published: 2026-07-19 15:40 – Updated: 2026-08-05 12:39
VLAI
Title
smb: client: protect tc_count increment in smb2_find_smb_sess_tcon_unlocked()
Summary
In the Linux kernel, the following vulnerability has been resolved: smb: client: protect tc_count increment in smb2_find_smb_sess_tcon_unlocked() Commit 96c4af418586 ("cifs: Fix locking usage for tcon fields") refactored cifs code to change cifs_tcp_ses_lock for tc_lock around tc_count changes. There was missing lock around tc_count increment inside smb2_find_smb_sess_tcon_unlocked().
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 953953abb66e52c224057ab91e404284fefeab62 , < 7df1df6f40c0720d30206aa35c0343b962350e0d (git)
Affected: 601dd3b79769b38d30b693c40afdb2a4b7edf9d0 , < 13fb413ae22a37c69341918a6d651d19a9b0b9b7 (git)
Affected: 3969db6b22e3d90d8c5f22ac1a7fe0350a94c136 , < bf4ebdb19ff9b3cdf992b50715fe61633327416a (git)
Affected: 96c4af418586ee9a6aab61738644366426e05316 , < e374f4e496fef8168784f93a4477d67be34485fd (git)
Affected: 96c4af418586ee9a6aab61738644366426e05316 , < 4d8690dace005a38e6dbde9ecce2da3ad85c7c41 (git)
Affected: 8c59eeeeffa1524ef57e173a89a1a3ff539888d5 (git)
Affected: 6.6.128 , < 6.6.142 (semver)
Affected: 6.12.75 , < 6.12.92 (semver)
Affected: 6.18.16 , < 6.18.34 (semver)
Affected: 6.19.6 , < 6.20 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 7.0
Unaffected: 0 , < 7.0 (semver)
Unaffected: 6.6.142 , ≤ 6.6.* (semver)
Unaffected: 6.12.92 , ≤ 6.12.* (semver)
Unaffected: 6.18.34 , ≤ 6.18.* (semver)
Unaffected: 7.0.11 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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      "status": "interim",
      "title": "SUSE CVE CVE-2026-64136",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64136.json",
      "version": "7"
    }
  }
}



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Tags
Taxonomy of the tags.





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.


Related by attack behaviour

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.