CVE-2009-1242: Canonical Ubuntu Linux

Medium severity, CVSS 4.9. EPSS: 0.5% chance of exploitation in the next 30 days.

The vmx_set_msr function in arch/x86/kvm/vmx.c in the VMX implementation in the KVM subsystem in the Linux kernel before 2.6.29.1 on the i386 platform allows guest OS users to cause a denial of service (OOPS) by setting the EFER_LME (aka "Long mode enable") bit in the Extended Feature Enable Register (EFER) model-specific register, which is specific to the x86_64 platform.

Affected products

• Canonical Ubuntu Linux: version 6.06 only; version 8.04 only; version 8.10 only; version 9.04 only
• Debian Debian Linux: version 4.0 only; version 5.0 only
• Fedoraproject Fedora: version 10 only
• Linux Linux Kernel: before 2.6.29.1 (fixed in 2.6.29.1)
• Opensuse Opensuse: version 11.0 only; version 11.1 only

Published 2009-04-06. Last modified 2026-06-16.