In the Linux kernel, the following vulnerability has been resolved:

KVM: TDX: Reject concurrent change to CPUID entry count

Reject KVM_TDX_INIT_VM if userspace changes cpuid.nent between the
initial read and the subsequent copy of the initialization data.

tdx_td_init() first reads user_data->cpuid.nent to size the flexible
kvm_tdx_init_vm copy. The copied structure also contains cpuid.nent,
and that field can differ from the value used to size the allocation if
userspace modifies the input concurrently. setup_tdparams_cpuids() later
passes init_vm->cpuid.nent to kvm_find_cpuid_entry2(), which uses it as
the array bound for the copied entries.

Require the copied count to match the value used to size the allocation
so that CPUID parsing cannot access beyond the entries actually copied.

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Sat, 15 Aug 2026 06:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: KVM: TDX: Reject concurrent change to CPUID entry count Reject KVM_TDX_INIT_VM if userspace changes cpuid.nent between the initial read and the subsequent copy of the initialization data. tdx_td_init() first reads user_data->cpuid.nent to size the flexible kvm_tdx_init_vm copy. The copied structure also contains cpuid.nent, and that field can differ from the value used to size the allocation if userspace modifies the input concurrently. setup_tdparams_cpuids() later passes init_vm->cpuid.nent to kvm_find_cpuid_entry2(), which uses it as the array bound for the copied entries. Require the copied count to match the value used to size the allocation so that CPUID parsing cannot access beyond the entries actually copied.
Title KVM: TDX: Reject concurrent change to CPUID entry count
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-08-15T05:55:08.385Z

Reserved: 2026-08-09T03:40:39.917Z

Link: CVE-2026-72285

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-15T06:21:59.700

Modified: 2026-08-15T06:21:59.700

Link: CVE-2026-72285

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

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