CVE-2026-64387 (GCVE-0-2026-64387)
Vulnerability from cvelistv5 – Published: 2026-07-25 08:50 – Updated: 2026-08-17 04:54
VLAI
EPSS
VEX
Title
smb: client: fix query directory replay double-free
Summary
In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix query directory replay double-free
A response-bearing attempt can return a replayable error and free its
response buffer. If SMB2_query_directory_init() fails before the next send,
cleanup retains the previous buffer type and frees that response again.
Reset response bookkeeping before each attempt to prevent the stale free.
Severity
9.8 (Critical)
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
433042a91f9373241307725b52de573933ffedbf , < 3409aedf3c81a810243da94164f6621c9d205c98
(git)
Affected: 4f1fffa2376922f3d1d506e49c0fd445b023a28e , < 1665f25b1dea30bf2d02e16245d203a944c9d994 (git) Affected: 4f1fffa2376922f3d1d506e49c0fd445b023a28e , < 00b0fa425941438b664950a8ee65dfba2def4336 (git) Affected: 4f1fffa2376922f3d1d506e49c0fd445b023a28e , < 3317a5d015fca976475aa71df224056777316fde (git) Affected: 4f1fffa2376922f3d1d506e49c0fd445b023a28e , < 9647492b5e41954be59d5157eddbcd4cdc1656f7 (git) Affected: 6.6.32 , < 6.6.145 (semver) |
guessed | |
| Linux | Linux |
Affected:
6.8
Unaffected: 0 , < 6.8 (semver) Unaffected: 6.6.145 , ≤ 6.6.* (semver) Unaffected: 6.12.96 , ≤ 6.12.* (semver) Unaffected: 6.18.39 , ≤ 6.18.* (semver) Unaffected: 7.1.4 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix) |
guessed |
{
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}
],
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}
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"date": "2026-09-15",
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"status": "final",
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"url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-64387.json",
"version": "2"
},
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"redhat_vex": {
"aggregate_severity": "Important",
"current_release_date": "2026-09-14T01:29:32+00:00",
"cve": "CVE-2026-64387",
"id": "CVE-2026-64387",
"initial_release_date": "2026-07-25T00:00:00+00:00",
"product_status:fixed": "919",
"product_status:known_affected": "22",
"product_status:known_not_affected": "90",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: smb: client: fix query directory replay double-free",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64387.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "important",
"current_release_date": "2026-09-15T01:50:23Z",
"cve": "CVE-2026-64387",
"id": "CVE-2026-64387",
"initial_release_date": "2026-07-25T16:00:19Z",
"product_status:first_fixed": "96",
"product_status:known_affected": "441",
"product_status:known_not_affected": "308",
"product_status:recommended": "129",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-64387",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64387.json",
"version": "12"
}
}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
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.
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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.
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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