OS Security: It's in the Chips

Microsoft's Windows XP Service Pack 2 and the next version of Red Hat's Enterprise Linux 3 will support new CPU-based security protections designed to stop incoming malicious executable code from being triggered.

The improved security feature has been included in 64-bit CPUs from Advanced Micro Devices since last year, but operating system makers haven't yet built support for the technology into their code, says Jeff Lowe, desktop marketing manager at Sunnyvale, California-based AMD.

That will change when Windows XP SP2 is released later this year and when Red Hat's new enterprise Linux OS ships in August.

Enhanced Protection

AMD calls its version of the new technology Enhanced Virus Protection. It was created by making changes to the silicon architecture in the processors that alter how code is permitted to enter and exit system memory, Lowe says. As a result, malicious code that acts in non-approved ways can be stopped at the gate.

"We think it's a great idea," he says. "You'll automatically get a level of security with it, then when you add security software you'll make it as hard as possible for hackers to get your company's data and your data. It's as many speed bumps as you can put in" to prevent attacks.

Red Hat is now working on the new NX, or "no execute," technology in prototype form for use with x86 processors from Intel and with Intel's 64-bit extension technology, says Tim Burke, director of server development at Raleigh, North Carolina-based Red Hat. NX prevents an operating system from executing malicious code at the CPU and memory levels so it can't infect a computer or system.

The NX technology is already present on Intel Itanium CPUs and is now in the prototype stages for x86 CPUs, he says.

Similar Security Feature

Red Hat is also working on a related security feature called Execshield, which is designed to help separate the program stack from its instruction area to prevent executables from erroneously being run in the event of an overflow, Burke says. Execshield also randomizes the memory address of a program stack to make it harder for malicious code to know where to gain entry into the program.

"This makes it almost impossible to figure where to put the malicious instructions," he says.

Dan Snyder, a spokesperson for Intel, says its Execute Disabled Bit security technology is already included in the company's Itanium CPUs. Support for the technology will also be built into Pentium 4 chips by the third quarter of this year, he says.

"It's not the be all and end all," Snyder says, but it should help prevent buffer underrun and other malicious attacks. "This basically prevents that by locking the operating system into not allowing it" to occur, he says.