CVE-2026-43096: linux kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: mshv: Fix infinite fault loop on permission-denied GPA intercepts Prevent infinite fault loops when guests access memory regions without proper permissions. Currently, mshv_handle_gpa_intercept() attempts to remap pages for all faults on movable memory regions, regardless of whether the access type is permitted. When a guest writes to a read-only region, the remap succeeds but the region remains read-only, causing immediate re-fault and spinning the vCPU indefinitely. Validate intercept access type against region permissions before attempting remaps. Reject writes to non-writable regions and executes to non-executable regions early, returning false to let the VMM handle the intercept appropriately. This also closes a potential DoS vector where malicious guests could intentionally trigger these fault loops to consume host resources.
CVE-2026-43096CVSS 5.5Linux

CVE-2026-43096: linux kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: mshv: Fix infinite fault loop on permission-denied GPA intercepts Prevent infinite fault loops when guests access memory regions without proper permissions. Currently, mshv_handle_gpa_intercept() attempts to remap pages for all faults on movable memory regions, regardless of whether the access type is permitted. When a guest writes to a read-only region, the remap succeeds but the region remains read-only, causing immediate re-fault and spinning the vCPU indefinitely. Validate intercept access type against region permissions before attempting remaps. Reject writes to non-writable regions and executes to non-executable regions early, returning false to let the VMM handle the intercept appropriately. This also closes a potential DoS vector where malicious guests could intentionally trigger these fault loops to consume host resources.

CVSS
5.5 MEDIUM
EPSS
1.39%
Known exploited
not in KEV
Product
linux kernel

What is known

In the Linux kernel, the following vulnerability has been resolved: mshv: Fix infinite fault loop on permission-denied GPA intercepts Prevent infinite fault loops when guests access memory regions without proper permissions. Currently, mshv_handle_gpa_intercept() attempts to remap pages for all faults on movable memory regions, regardless of whether the access type is permitted. When a guest writes to a read-only region, the remap succeeds but the region remains read-only, causing immediate re-fault and spinning the vCPU indefinitely. Validate intercept access type against region permissions before attempting remaps. Reject writes to non-writable regions and executes to non-executable regions early, returning false to let the VMM handle the intercept appropriately. This also closes a potential DoS vector where malicious guests could intentionally trigger these fault loops to consume host resources.

Sources

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