CVE-2026-64562 KVM: nVMX: Hide shadow VMCS right after VMCLEAR
A use-after-free vulnerability in the Linux kernel's KVM nVMX implementation allows attackers to potentially execute code or escalate privileges via improper shadow VMCS handling.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-64562?
CVE-2026-64562 is a high-severity use after free vulnerability in Linux, published on 4 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Weakness: CWE-416
Which versions are affected by CVE-2026-64562?
How do I fix CVE-2026-64562?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-64562 being exploited?
There is no known exploitation of CVE-2026-64562 in the wild and no public exploit code.
Sources
Also known as AZL-94404, BELL-CVE-2026-64562, DEBIAN-CVE-2026-64562, GHSA-mc77-r35g-cpmm, UBUNTU-CVE-2026-64562.