Hackers compromised free CCleaner software

San Francisco

HACKERS broke into British company Piriform's free software for optimising computer performance last month, potentially allowing them to control the devices of more than two million users, the company and independent researchers said on Monday.

The malicious program was slipped into legitimate software called CCleaner, which is downloaded for personal computers and Android phones as often as five million times a week. It cleans up junk programs and advertising cookies to speed up devices.