Improper Initialization in Linux kernel - CVE-2026-64513
Published: July 27, 2026
Vulnerability identifier: #VU139422
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-64513
CWE-ID: CWE-665
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper state management in KVM x86 LAPIC and CR8 intercept handling when updating the guest's PPR and entering a virtual machine. A local user can trigger PPR updates in a guest to cause a VM entry failure with hardware error 0x7.
This is typically exposed on older platforms or under nested virtualization on a hypervisor that does not support virtual-interrupt delivery and enforces the TPR_THRESHOLD check.
Affected software
Linux kernel
How to mitigate CVE-2026-64513
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3