CVE-2009-4031: Linux Kernel

High severity, CVSS 7.8. EPSS: 3.1% chance of exploitation in the next 30 days.

The do_insn_fetch function in arch/x86/kvm/emulate.c in the x86 emulator in the KVM subsystem in the Linux kernel before 2.6.32-rc8-next-20091125 tries to interpret instructions that contain too many bytes to be valid, which allows guest OS users to cause a denial of service (increased scheduling latency) on the host OS via unspecified manipulations related to SMP support.

Affected products

• Linux Linux Kernel: before 2.6.32 (fixed in 2.6.32); version 2.6.32 only

Published 2009-11-29. Last modified 2026-06-16.