Qemu-kvm: vapic writable rom alias can escape the option-rom window and expose locked smram
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.2epss 0.2%
exploitation probability
0.2%top 90% of all CVEs
observed exploitation
nono source reports it
A flaw was found in QEMU. The VAPIC setup hypercall in hw/i386/vapic.c does not validate that the writable RAM alias remains within the option ROM window. A privileged guest user on a Q35/KVM machine can position this alias over locked SMRAM, bypassing chipset D_LCK protection and injecting code into System Management Mode memory.
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Affected products
Red Hat · Red Hat Enterprise Linux 10Red Hat · Red Hat Enterprise Linux 6Red Hat · Red Hat Enterprise Linux 7Red Hat · Red Hat Enterprise Linux 8Red Hat · Red Hat Enterprise Linux 9Red Hat · Red Hat Enterprise Linux for NVIDIA 26Red Hat · Red Hat OpenShift Container Platform 4Red Hat · Red Hat OpenStack Platform 13 (Queens)