Google has yet to bring its U.S. success to China--only about one in five Chinese Web searches starts at the site. But lately, Google seems to have gained popularity with at least one group of Chinese Web users: some of the country's most successful cybercriminals.

Over the past several weeks, researchers have tracked a hacker exploit that's infected more than half a million pages around the Web, invisibly redirecting visitors to those pages to servers that install malicious software on their PCs. The cybercriminals' exploit uses an increasingly common method to decide which pages to infect: Google (nasdaq: GOOG - news - people ) searches that probe sites en masse for hackable weak points.

According to those who have followed the attack at the SANS Institute's Internet Storm Center, a cybersecurity crisis response organization, the infection tool is partially written in Chinese characters and compiled on a computer with Chinese language settings.