CVE-2026-64136 (GCVE-0-2026-64136)
Vulnerability from cvelistv5 – Published: 2026-07-19 15:40 – Updated: 2026-08-05 12:39
VLAI
EPSS
VEX
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)
Assigner
References
Impacted products
2 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 | |
| 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 |
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"id": "CVE-2026-64136",
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"source": "SUSE CSAF VEX",
"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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}
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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- 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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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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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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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