CVE-2026-64284

In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Ensure vendor's exit handler runs before fastpath userspace exits Move the handling of fastpath userspace exits into vendor code to ensure KVM runs vendor specific operations that need to run before userspace gains control of the vCPU. E.g. for VMX (and soon to be for SVM as well), KVM needs to flush the PML buffer prior to exiting to userspace, otherwise any memory written by the final KVM_RUN might never be flagged as dirty. Note, waiting to snapshot CR0 and CR3 until svm_handle_exit() is flawed in general, as that risks consuming stale state in a fastpath handler. That will be addressed in a future change.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/0ffedf43910e44b76c2c1db4e9fbf12b268190c1	Patch
https://git.kernel.org/stable/c/4ad73ef0e7966ecfe67de0060537b4cb14d9acd4	Patch
https://git.kernel.org/stable/c/b3436d9b9b1affe1c3191ac9831308923f5f03c3	Patch
https://git.kernel.org/stable/c/f2ca2b5326211bd38490f0497eb583721ce0bbc0	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2026-07-25 10:17

Updated : 2026-08-17 05:17

NVD link : CVE-2026-64284

Mitre link : CVE-2026-64284

CVE.ORG link : CVE-2026-64284

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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