CVE-2026-98863

high

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.

References

https://git.kernel.org/stable/c/942192dbcd3a06695ef6b31cf10a41a21cf014d8

https://git.kernel.org/stable/c/525694a6021ec6c8f7ce1f38acdf2dd77698fec1

https://git.kernel.org/stable/c/10180a277549339020b08000206092c07e0bff5a

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-103803

Details

Source: Mitre, NVD

Published: 2026-10-18

Updated: 2026-10-19

Risk Information

CVSS v2

Base Score: 5.6

Vector: CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:C

Severity: Medium

CVSS v3

Base Score: 7.1

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Severity: High