CVEvulnerability
CVE-2026-98863
- Status
- Received
- Published
- 2026-10-18
- Last modified
- 2026-10-19
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: Re-pend GET_NESTED_STATE_PAGES if getting said pages fails
Re-pend GET_NESTED_STATE_PAGES before exiting to userspace if getting the
nested pages fails in the KVM_RUN path. If userspace re-runs the vCPU, and
vmcs02 holds valid PFNs from the *previous* run of L2, then KVM could
re-enter L2 with stale, unpinned PFNs mapped into e.g. the vAPIC page.
Note, both SVM and VMX (as of commit 11722439fb20 ("KVM: nVMX: Ensure
KVM_REQ_GET_NESTED_STATE_PAGES is cleared on VM-Exit") ensure the request
is cleared on VM-Exit (including the "forced" case), i.e. there is no risk
of double-mapping due to emulated VMLAUNCH/VMRESUME/VMRUN *and* the request
trying to map the nested pages.