Microsoft prepares for mobile virus battle

Besides ring tones and wallpapers, you could soon be downloading virus definitions over the airwaves as part of Microsoft's defence against a possible mobile phone virus outbreak.

To allay such fears, Microsoft has built multiple security features into its Smartphone OS, a Symbian rival which is also used in hybrid devices which blends the functions of a mobile phone with a personal digital assistant, claimed Mike Wehrs, director of technology and standards for Microsoft's Mobile Devices Division.

If all else fails and the worm manages to proliferate, patches for Windows-based smart phones can be distributed and downloaded quickly via cellular networks to curb the outbreak, he said at the sidelines of the CommunicAsia trade show here.

"If something is found and is identified as a vulnerability, we can distribute updated code for the phone over the internet and over the air," Wehrs said. "We try to short-circuit how fast the virus spreads by updating it [the OS] in the field."

However, he is skeptical such en-masse patching would be necessary, as malicious programs stand "remote chances" of bypassing the Smartphone OS's digital certification feature.

According to Wehrs, applications designed for Windows smart phones can be digitally-signed to ensure their legitimacy. Handset makers or mobile operators can implement policies to prevent users from running unsigned applications on their devices, he added.

"Even if the handset OEM (Original Equipment Manufacturer) or operator decides not to turn those security features on, every piece of code that attempts execute on the phone triggers a dialogue box," Wehrs stressed. "The likelihood of someone writing a piece of code that actually could duplicate and get around the certificate system is pretty remote."

This approach is also favored by Symbian, which launched its application-certification scheme last month. Coined "Symbian Signed", the program is backed by ardent supporters of the OS including Sony Ericsson, Nokia and Sendo.

Winston Chai writes for CNETAsia