Database/Kernel, userspace & hypervisor
Linux KVM x86 - stack out-of-bounds in ioapic_write_indirect(): MULTI-TENANT ISOLATION: A guest write to the virtual
Impact
MULTI-TENANT ISOLATION: A guest write to the virtual IOAPIC causes a stack out-of-bounds access in the host kernel, reported by KASAN. At CVSS 8.8 this is a guest-to-host memory corruption primitive reachable by writing to an emulated device every VM has - stack corruption in the hypervisor is the shortest path from one tenant's VM to owning the machine and everything else on it.
Who can reach it
From inside a guest VM, by writing to the emulated IOAPIC. Tenant-reachable with no privilege beyond running a VM.
What to do
Fixed in the Linux kernel. Distro kernel update plus host reboot - no firmware, no VBIOS. Treat as top priority on any host running untrusted guest VMs.
References
This entry is curated: imported from vendor advisories with machine assistance, not yet individually verified. Confirm against your vendor's advisory before acting, and report anything wrong.