Linux Kernel up to 7.2-rc2 legousbtower mutex_unlock use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.4$0-$5k3.11-

Summaryinfo

A vulnerability marked as very critical has been reported in Linux Kernel up to 7.2-rc2. Impacted is the function mutex_unlock of the component legousbtower. The manipulation leads to use after free. This vulnerability is referenced as CVE-2026-64340. The attack can only be performed from a local environment. No exploit is available.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.2-rc2 and classified as very critical. This issue affects the function mutex_unlock of the component legousbtower. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: USB: legousbtower: fix use-after-free on disconnect race mutex_unlock() may access the mutex structure after releasing the lock and therefore cannot be used to manage lifetime of objects directly (unlike spinlocks and refcounts). [1][2] Use a kref to release the driver data to avoid use-after-free in mutex_unlock() when release() races with disconnect(). [1] a51749ab34d9 ("locking/mutex: Document that mutex_unlock() is non-atomic") [2] 2b9d9e0a9ba0 ("locking/mutex: Clarify that mutex_unlock(), and most other sleeping locks, can still use the lock object after it's unlocked")

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2026-64340 since 07/19/2026. The exploitation is known to be easy. Attacking locally is a requirement. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/25/2026).

Upgrading to version 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39, 7.1.4 or 7.2-rc3 eliminates this vulnerability. Applying the patch 11d069f85851997b4ea0adf242ed9672dc749b8f/b4222c05066b252b451f9c8c4730b5b60824ea66/6462de75d2e370c7e74dcfb7b4ae79eb5a6a55ee/0b57e5ddbd89df3bc367463de3d2ca66f99a1a5e/ab2bfd7bec4f134b377ec42f513e90c35db94160/766738ecf2b819e54d38763c8d1c8ae6cff14b39/9ba62966461a8e3cc593b62c56ec62eb2d80436d/62fc8eb1b1481051f7bab4aa93d79809053dd09f is able to eliminate this problem.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.8
VulDB Meta Temp Score: 8.4

VulDB Base Score: 8.8
VulDB Temp Score: 8.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.261/5.15.212/6.1.178/6.6.145/6.12.96/6.18.39/7.1.4/7.2-rc3
Patch: 11d069f85851997b4ea0adf242ed9672dc749b8f/b4222c05066b252b451f9c8c4730b5b60824ea66/6462de75d2e370c7e74dcfb7b4ae79eb5a6a55ee/0b57e5ddbd89df3bc367463de3d2ca66f99a1a5e/ab2bfd7bec4f134b377ec42f513e90c35db94160/766738ecf2b819e54d38763c8d1c8ae6cff14b39/9ba62966461a8e3cc593b62c56ec62eb2d80436d/62fc8eb1b1481051f7bab4aa93d79809053dd09f

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-2026-64340 (🔒)
GCVE (CVE): GCVE-0-2026-64340
GCVE (VulDB): GCVE-100-383135

Entryinfo

Created: 07/25/2026 16:01
Changes: 07/25/2026 16:01 (59)
Complete: 🔍
Cache ID: 216::103

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