Linux Kernel up to 7.2-rc4 nVMX free_nested race condition

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$0-$5k0.64+

Summaryinfo

A vulnerability, which was classified as very critical, has been found in Linux Kernel up to 6.6.147/6.12.100/6.18.41/7.1.5/7.2-rc4. Affected by this issue is the function free_nested of the component nVMX. This manipulation causes race condition. This vulnerability is handled as CVE-2026-64562. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.6.147/6.12.100/6.18.41/7.1.5/7.2-rc4 and classified as very critical. Affected by this vulnerability is the function free_nested of the component nVMX. The manipulation with an unknown input leads to a race condition vulnerability. The CWE definition for the vulnerability is CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: KVM: nVMX: Hide shadow VMCS right after VMCLEAR free_nested() frees the shadow VMCS while vmcs01 still points to it. But because it is asynchronous with respect to loaded_vmcs_clear(), the vCPU might migrate before the pointer is cleared and __loaded_vmcs_clear() may then execute VMCLEAR. The VMCS needs to stay attached until its explicit VMCLEAR completes, but then it can be hidden and the page safely freed.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2026-64562 since 07/19/2026. The exploitation appears to be easy. The attack can be launched remotely. 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 08/04/2026).

Upgrading to version 6.6.148, 6.12.101, 6.18.42, 7.1.6 or 7.2-rc5 eliminates this vulnerability. Applying the patch af56298e9d86e6098cd1d2e155cb2949b7c45412/589419470030a89f16cf19300658b6dc644ca946/8001d2ce9d9bd09118ce523aef595aa094573ae3/1dabef6e206568bf9d9ade74f6e56a48ea35695d/622ebfac01ba4f9c0060cebd41257fe46fc4a0b3 is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-52603). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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

Exploitinginfo

Class: Race condition
CWE: CWE-362
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
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 6.6.148/6.12.101/6.18.42/7.1.6/7.2-rc5
Patch: af56298e9d86e6098cd1d2e155cb2949b7c45412/589419470030a89f16cf19300658b6dc644ca946/8001d2ce9d9bd09118ce523aef595aa094573ae3/1dabef6e206568bf9d9ade74f6e56a48ea35695d/622ebfac01ba4f9c0060cebd41257fe46fc4a0b3

Timelineinfo

07/19/2026 CVE reserved
08/04/2026 +16 days Advisory disclosed
08/04/2026 +0 days VulDB entry created
08/04/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64562 (🔒)
GCVE (CVE): GCVE-0-2026-64562
GCVE (VulDB): GCVE-100-385771
EUVD: 🔒

Entryinfo

Created: 08/04/2026 09:05
Updated: 08/04/2026 09:16
Changes: 08/04/2026 09:05 (59), 08/04/2026 09:16 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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