CVE-2022-50224
Unknown Unknown - Not Provided
BaseFortify

Publication date: 2025-06-18

Last updated on: 2025-11-19

Assigner: kernel.org

Description
In the Linux kernel, the following vulnerability has been resolved: KVM: x86/mmu: Treat NX as a valid SPTE bit for NPT Treat the NX bit as valid when using NPT, as KVM will set the NX bit when the NX huge page mitigation is enabled (mindblowing) and trigger the WARN that fires on reserved SPTE bits being set. KVM has required NX support for SVM since commit b26a71a1a5b9 ("KVM: SVM: Refuse to load kvm_amd if NX support is not available") for exactly this reason, but apparently it never occurred to anyone to actually test NPT with the mitigation enabled. ------------[ cut here ]------------ spte = 0x800000018a600ee7, level = 2, rsvd bits = 0x800f0000001fe000 WARNING: CPU: 152 PID: 15966 at arch/x86/kvm/mmu/spte.c:215 make_spte+0x327/0x340 [kvm] Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 10.48.0 01/27/2022 RIP: 0010:make_spte+0x327/0x340 [kvm] Call Trace: <TASK> tdp_mmu_map_handle_target_level+0xc3/0x230 [kvm] kvm_tdp_mmu_map+0x343/0x3b0 [kvm] direct_page_fault+0x1ae/0x2a0 [kvm] kvm_tdp_page_fault+0x7d/0x90 [kvm] kvm_mmu_page_fault+0xfb/0x2e0 [kvm] npf_interception+0x55/0x90 [kvm_amd] svm_invoke_exit_handler+0x31/0xf0 [kvm_amd] svm_handle_exit+0xf6/0x1d0 [kvm_amd] vcpu_enter_guest+0xb6d/0xee0 [kvm] ? kvm_pmu_trigger_event+0x6d/0x230 [kvm] vcpu_run+0x65/0x2c0 [kvm] kvm_arch_vcpu_ioctl_run+0x355/0x610 [kvm] kvm_vcpu_ioctl+0x551/0x610 [kvm] __se_sys_ioctl+0x77/0xc0 __x64_sys_ioctl+0x1d/0x20 do_syscall_64+0x44/0xa0 entry_SYSCALL_64_after_hwframe+0x46/0xb0 </TASK> ---[ end trace 0000000000000000 ]---
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2025-06-18
Last Modified
2025-11-19
Generated
2026-05-07
AI Q&A
2025-06-18
EPSS Evaluated
2026-05-05
NVD
Affected Vendors & Products
Showing 7 associated CPEs
Vendor Product Version / Range
linux linux_kernel From 5.15.160 (inc) to 5.16 (inc)
linux linux_kernel From 5.15.160 (inc) to 5.16 (inc)
linux linux_kernel From 5.15.160 (inc) to 5.16 (inc)
linux linux_kernel 5.4
linux linux_kernel 5.4
linux linux_kernel From 5.15.160 (inc) to 5.16 (inc)
linux linux_kernel From 5.15.160 (inc) to 5.16 (inc)
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-NVD-CWE-noinfo
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?

This vulnerability involves the Linux kernel's KVM (Kernel-based Virtual Machine) on x86 architectures, specifically in the memory management unit (MMU) handling of nested page tables (NPT). The issue was that the NX (No Execute) bit was not treated as a valid shadow page table entry (SPTE) bit when NPT was used. KVM sets the NX bit when the NX huge page mitigation is enabled, which caused a warning due to reserved bits being set incorrectly. The fix treats the NX bit as valid for NPT, preventing these warnings and potential issues in virtualization environments.


How can this vulnerability impact me? :

This vulnerability could cause warnings and potential instability in virtualized environments using KVM with nested page tables and NX huge page mitigation enabled. It may lead to unexpected behavior or crashes in virtual machines due to improper handling of the NX bit in page tables, affecting system reliability and performance in virtualization scenarios.


Ask Our AI Assistant
Need more information? Ask your question to get an AI reply (Powered by our expertise)
0/70
EPSS Chart