Linux Kernel up to 6.6.144/6.12.95/6.18.38/7.1.3 SMB Client SMB2_notify_init double free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$5k-$25k2.32-

Summaryinfo

A vulnerability classified as very critical was found in Linux Kernel up to 6.6.144/6.12.95/6.18.38/7.1.3. The affected element is the function SMB2_notify_init of the component SMB Client. Such manipulation leads to double free. This vulnerability is referenced as CVE-2026-64384. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.6.144/6.12.95/6.18.38/7.1.3 and classified as very critical. Affected by this issue is the function SMB2_notify_init of the component SMB Client. The manipulation with an unknown input leads to a double free vulnerability. Using CWE to declare the problem leads to CWE-415. The product calls free() twice on the same memory address, potentially leading to modification of unexpected memory locations. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix change notify replay double-free A response-bearing attempt can return a replayable error and free its response buffer. If SMB2_notify_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.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2026-64384 since 07/19/2026. The exploitation is known to be easy. The attack may be launched remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 07/25/2026).

Upgrading to version 6.6.145, 6.12.96, 6.18.39, 7.1.4 or 7.2-rc1 eliminates this vulnerability. Applying the patch 5821f9dbb8b5b24391850a13418e633edd0fb003/d684f4134998085702009b94c35c2003fc9e72d3/52af1975f0dfae990c5a0e85872cc41be0e88a68/901891513951bc8322ece754863909ea45af95c6/145f820dcbb2cced374f2532f8a61a44dce4a615 is able to eliminate this problem.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Double free
CWE: CWE-415 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.6.145/6.12.96/6.18.39/7.1.4/7.2-rc1
Patch: 5821f9dbb8b5b24391850a13418e633edd0fb003/d684f4134998085702009b94c35c2003fc9e72d3/52af1975f0dfae990c5a0e85872cc41be0e88a68/901891513951bc8322ece754863909ea45af95c6/145f820dcbb2cced374f2532f8a61a44dce4a615

Timelineinfo

07/19/2026 CVE reserved
07/25/2026 +6 days Advisory disclosed
07/25/2026 +0 days VulDB entry created
07/25/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64384 (🔒)
GCVE (CVE): GCVE-0-2026-64384
GCVE (VulDB): GCVE-100-383180

Entryinfo

Created: 07/25/2026 18:07
Changes: 07/25/2026 18:07 (59)
Complete: 🔍
Cache ID: 216::103

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