On one hand, a new study by security firm BitDefender points out that "Windows 8 is prone to infection by some 15 percent of the 100 malware families most used by cyber criminals this year, even with Windows Defender activated." BitDefender tossed 385 of the most popular malware samples at a Windows 8 testbed, with Windows Defender running, and it fell prey to 61 of the threats. Without Windows Defender activated, the Windows 8 machine allowed 234 of the malware samples to run successfully.
"As a means of protecting a computer from viruses, data theft and other type of malware, Windows Defender is better than nothing," said Bitdefender Chief Security Strategist Catalin Cosoi. "But it’s not a whole lot better. Most of the popular antivirus can do better. The conclusion is clear: Using your PC without a security solution is extremely risky."
Obviously BitDefender has a vested interest in studies like this, since it sells security software, but the fact that Windows 8 (with Windows Defender) defends against 85 percent of the most popular threats out there is pretty encouraging. Plus, protection will improve over time as Microsoft releases more definition updates. Even a 5 percent improvement would mean that Windows 8 would then be thwarting 9 out of 10 of the most popular malware samples.