A flaw in some 64-bit operating systems and virtualization software programs are vulnerable to local privilege escalation attacks.
The problem only happens when running on Intel processors, the US Computer Emergency Readiness Team (US-CERT) announced today. The hole, dubbed CVE-2012-0217, stems from the way Intel CPUs have implemented the SYSRET instruction in their x86-64 extension, known as Intel 64.
Crackers could exploit the vulnerability to force Intel CPUs to return a general protection fault in privileged mode. This would give them power to execute code with kernel privileges from a least-privileged account, or to escape from a virtual machine and gain control of the host operating system.
The vulnerability can only be exploited on Intel CPUs when the Intel 64 extension is in use. Some of the operating systems confirmed as vulnerable so far include x64-based versions of Windows 7 and Windows Server 2008 R2, the 64-bit versions of FreeBSD and NetBSD, the Xen virtualisation software, as well as Red Hat Enterprise Linux and SUSE Linux Enterprise Server.