CVE-2023-53756
published 2025-12-08CVE-2023-53756: In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Fix crash due to uninitialized current_vmcs KVM enables 'Enlightened VMCS' and…
PriorityP422medium5.5
EPSS
0.19%
8.5th percentile
In the Linux kernel, the following vulnerability has been resolved:
KVM: VMX: Fix crash due to uninitialized current_vmcs
KVM enables 'Enlightened VMCS' and 'Enlightened MSR Bitmap' when running as
a nested hypervisor on top of Hyper-V. When MSR bitmap is updated,
evmcs_touch_msr_bitmap function uses current_vmcs per-cpu variable to mark
that the msr bitmap was changed.
vmx_vcpu_create() modifies the msr bitmap via vmx_disable_intercept_for_msr
-> vmx_msr_bitmap_l01_changed which in the end calls this function. The
function checks for current_vmcs if it is null but the check is
insufficient because current_vmcs is not initialized. Because of this, the
code might incorrectly write to the structure pointed by current_vmcs value
left by another task. Preemption is not disabled, the current task can be
preempted and moved to another CPU while current_vmcs is accessed multiple
times from evmcs_touch_msr_bitmap() which leads to crash.
The manipulation of MSR bitmaps by callers happens only for vmcs01 so the
solution is to use vmx->vmcs01.vmcs instead of current_vmcs.
BUG: kernel NULL pointer dereference, address: 0000000000000338
PGD 4e1775067 P4D 0
Oops: 0002 [#1] PREEMPT SMP NOPTI
...
RIP: 0010:vmx_msr_bitmap_l01_changed+0x39/0x50 [kvm_intel]
...
Call Trace:
vmx_disable_intercept_for_msr+0x36/0x260 [kvm_intel]
vmx_vcpu_create+0xe6/0x540 [kvm_intel]
kvm_arch_vcpu_create+0x1d1/0x2e0 [kvm]
kvm_vm_ioctl_create_vcpu+0x178/0x430 [kvm]
kvm_vm_ioctl+0x53f/0x790 [kvm]
__x64_sys_ioctl+0x8a/0xc0
do_syscall_64+0x5c/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Affected
15 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.1.20-1 (bookworm) | linux 6.1.20-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= ceef7d10dfb6284d512c499292e6daa35ea83f90 < 6baebcecf09acd19e2bab1c2911dcdba5d48a1dc | 6baebcecf09acd19e2bab1c2911dcdba5d48a1dc |
| linux | linux | >= ceef7d10dfb6284d512c499292e6daa35ea83f90 < 6e7bc50f97c9855da83f1478f722590defd45ff2 | 6e7bc50f97c9855da83f1478f722590defd45ff2 |
| linux | linux | >= ceef7d10dfb6284d512c499292e6daa35ea83f90 < b2de2b4d4e007f9add46ea8dc06f781835e3ea9f | b2de2b4d4e007f9add46ea8dc06f781835e3ea9f |
| linux | linux | >= ceef7d10dfb6284d512c499292e6daa35ea83f90 < 3ba95cc671c025d0d2a1c7d5e2930f0ff0980cf4 | 3ba95cc671c025d0d2a1c7d5e2930f0ff0980cf4 |
| linux | linux | >= ceef7d10dfb6284d512c499292e6daa35ea83f90 < 93827a0a36396f2fd6368a54a020f420c8916e9b | 93827a0a36396f2fd6368a54a020f420c8916e9b |
| linux | linux_kernel | >= 0 < 5.10.178-1 | 5.10.178-1 |
| linux | linux_kernel | >= 0 < 6.1.20-1 | 6.1.20-1 |
| linux | linux_kernel | >= 0 < 6.1.20-1 | 6.1.20-1 |
| linux | linux_kernel | >= 0 < 6.1.20-1 | 6.1.20-1 |
| linux | linux_kernel | >= 4.18.0 < 5.10.175 | 5.10.175 |
| linux | linux_kernel | >= 5.11.0 < 5.15.103 | 5.15.103 |
| linux | linux_kernel | >= 5.16.0 < 6.1.16 | 6.1.16 |
| linux | linux_kernel | >= 6.2.0 < 6.2.3 | 6.2.3 |
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OSV
KVM: VMX: Fix crash due to uninitialized current_vmcs
osv·2025-12-08
CVE-2023-53756 KVM: VMX: Fix crash due to uninitialized current_vmcs
KVM: VMX: Fix crash due to uninitialized current_vmcs
In the Linux kernel, the following vulnerability has been resolved:
KVM: VMX: Fix crash due to uninitialized current_vmcs
KVM enables 'Enlightened VMCS' and 'Enlightened MSR Bitmap' when running as
a nested hypervisor on top of Hyper-V. When MSR bitmap is updated,
evmcs_touch_msr_bitmap function uses current_vmcs per-cpu variable to mark
that the msr bitmap was changed.
vmx_vcpu_create() modifies the msr bitmap via vmx_disable_intercept_for_msr
-> vmx_msr_bitmap_l01_changed which in the end calls this function. The
function checks for current_vmcs if it is null but the check is
insufficient because current_vmcs is not initialized. Because of this, the
code might incorrectly write to the structure pointed by current_vmcs value
left b
OSV
CVE-2023-53756: In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Fix crash due to uninitialized current_vmcs KVM enables 'Enlightened VMC
osv·2025-12-08
CVE-2023-53756 CVE-2023-53756: In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Fix crash due to uninitialized current_vmcs KVM enables 'Enlightened VMC
In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Fix crash due to uninitialized current_vmcs KVM enables 'Enlightened VMCS' and 'Enlightened MSR Bitmap' when running as a nested hypervisor on top of Hyper-V. When MSR bitmap is updated, evmcs_touch_msr_bitmap function uses current_vmcs per-cpu variable to mark that the msr bitmap was changed. vmx_vcpu_create() modifies the msr bitmap via vmx_disable_intercept_for_msr -> vmx_msr_bitmap_l01_changed which in the end calls this function. The function checks for current_vmcs if it is null but the check is insufficient because current_vmcs is not initialized. Because of this, the code might incorrectly write to the structure pointed by current_vmcs value left by another task. Preemption is not disabled, the current ta
GHSA
GHSA-5h86-42q5-w9hr: In the Linux kernel, the following vulnerability has been resolved:
KVM: VMX: Fix crash due to uninitialized current_vmcs
KVM enables 'Enlightened V
ghsa_unreviewed·2025-12-08
CVE-2023-53756 GHSA-5h86-42q5-w9hr: In the Linux kernel, the following vulnerability has been resolved:
KVM: VMX: Fix crash due to uninitialized current_vmcs
KVM enables 'Enlightened V
In the Linux kernel, the following vulnerability has been resolved:
KVM: VMX: Fix crash due to uninitialized current_vmcs
KVM enables 'Enlightened VMCS' and 'Enlightened MSR Bitmap' when running as
a nested hypervisor on top of Hyper-V. When MSR bitmap is updated,
evmcs_touch_msr_bitmap function uses current_vmcs per-cpu variable to mark
that the msr bitmap was changed.
vmx_vcpu_create() modifies the msr bitmap via vmx_disable_intercept_for_msr
-> vmx_msr_bitmap_l01_changed which in the end calls this function. The
function checks for current_vmcs if it is null but the check is
insufficient because current_vmcs is not initialized. Because of this, the
code might incorrectly write to the structure pointed by current_vmcs value
left by another task. Preemption is not disabled, the current
Red Hat
kernel: KVM: VMX: Fix crash due to uninitialized current_vmcs
vendor_redhat·2025-12-08·CVSS 5.5
CVE-2023-53756 [MEDIUM] CWE-824 kernel: KVM: VMX: Fix crash due to uninitialized current_vmcs
kernel: KVM: VMX: Fix crash due to uninitialized current_vmcs
In the Linux kernel, the following vulnerability has been resolved:
KVM: VMX: Fix crash due to uninitialized current_vmcs
KVM enables 'Enlightened VMCS' and 'Enlightened MSR Bitmap' when running as
a nested hypervisor on top of Hyper-V. When MSR bitmap is updated,
evmcs_touch_msr_bitmap function uses current_vmcs per-cpu variable to mark
that the msr bitmap was changed.
vmx_vcpu_create() modifies the msr bitmap via vmx_disable_intercept_for_msr
-> vmx_msr_bitmap_l01_changed which in the end calls this function. The
function checks for current_vmcs if it is null but the check is
insufficient because current_vmcs is not initialized. Because of this, the
code might incorrectly write to the structure pointed by current_vmcs value
l
Debian
CVE-2023-53756: linux - In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: F...
vendor_debian·2023
CVE-2023-53756 CVE-2023-53756: linux - In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: F...
In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Fix crash due to uninitialized current_vmcs KVM enables 'Enlightened VMCS' and 'Enlightened MSR Bitmap' when running as a nested hypervisor on top of Hyper-V. When MSR bitmap is updated, evmcs_touch_msr_bitmap function uses current_vmcs per-cpu variable to mark that the msr bitmap was changed. vmx_vcpu_create() modifies the msr bitmap via vmx_disable_intercept_for_msr -> vmx_msr_bitmap_l01_changed which in the end calls this function. The function checks for current_vmcs if it is null but the check is insufficient because current_vmcs is not initialized. Because of this, the code might incorrectly write to the structure pointed by current_vmcs value left by another task. Preemption is not disabled, the current ta
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/3ba95cc671c025d0d2a1c7d5e2930f0ff0980cf4https://git.kernel.org/stable/c/6baebcecf09acd19e2bab1c2911dcdba5d48a1dchttps://git.kernel.org/stable/c/6e7bc50f97c9855da83f1478f722590defd45ff2https://git.kernel.org/stable/c/93827a0a36396f2fd6368a54a020f420c8916e9bhttps://git.kernel.org/stable/c/b2de2b4d4e007f9add46ea8dc06f781835e3ea9f
2025-12-08
Published