In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Fix ID register initialization for non-protected pKVM guests
In protected mode, the hypervisor maintains a separate instance of
the `kvm` structure for each VM. For non-protected VMs, this structure is
initialized from the host's `kvm` state.
Currently, `pkvm_init_features_from_host()` copies the
`KVM_ARCH_FLAG_ID_REGS_INITIALIZED` flag from the host without the
underlying `id_regs` data being initialized. This results in the
hypervisor seeing the flag as set while the ID registers remain zeroed.
Consequently, `kvm_has_feat()` checks at EL2 fail (return 0) for
non-protected VMs. This breaks logic that relies on feature detection,
such as `ctxt_has_tcrx()` for TCR2_EL1 support. As a result, certain
system registers (e.g., TCR2_EL1, PIR_EL1, POR_EL1) are not
saved/restored during the world switch, which could lead to state
corruption.
Fix this by explicitly copying the ID registers from the host `kvm` to
the hypervisor `kvm` for non-protected VMs during initialization, since
we trust the host with its non-protected guests' features. Also ensure
`KVM_ARCH_FLAG_ID_REGS_INITIALIZED` is cleared initially in
`pkvm_init_features_from_host` so that `vm_copy_id_regs` can properly
initialize them and set the flag once done.
References
Configurations
Configuration 1 (hide)
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History
21 Jul 2026, 19:10
| Type | Values Removed | Values Added |
|---|---|---|
| Summary |
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27 Apr 2026, 14:16
| Type | Values Removed | Values Added |
|---|---|---|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 8.8 |
23 Apr 2026, 21:04
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://git.kernel.org/stable/c/7e7c2cf0024d89443a7af52e09e47b1fe634ab17 - Patch | |
| References | () https://git.kernel.org/stable/c/858620655c1fbff05997e162fc7d83a3293d5142 - Patch | |
| References | () https://git.kernel.org/stable/c/bce3847f7c51b86332bf2e554c9e80ca3820f16c - Patch | |
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 5.5 |
| CPE | cpe:2.3:o:linux:linux_kernel:6.14:-:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:* |
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| First Time |
Linux
Linux linux Kernel |
|
| CWE | NVD-CWE-noinfo |
03 Apr 2026, 14:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-04-03 14:16
Updated : 2026-07-21 19:10
NVD link : CVE-2026-23425
Mitre link : CVE-2026-23425
CVE.ORG link : CVE-2026-23425
JSON object : View
Products Affected
linux
- linux_kernel
CWE
