Five Web sites run by Chinese human rights activists were attacked by hackers over the weekend, as a separate row continued between Google and China over political cyberattacks.
The Web site of Chinese Human Rights Defenders, an advocacy group, was hit by a distributed denial of service (DDoS) attack that lasted 16 hours starting Saturday afternoon, the group said in an e-mailed statement today.
A DDoS attack involves the attacker ordering a legion of compromised computers all to visit a certain Web site at once, overwhelming its server with requests for communication and leaving the site inaccessible to normal visitors. The group said it could not confirm the origin of the attackers but called the Chinese government the most likely suspect.
Google this month said it had been hit by cyberattacks from China partly aimed at accessing the Gmail accounts of human rights activists. The company cited the attacks, which also resulted in the theft of Google intellectual property, as one reason it plans to stop censoring its Chinese search engine, even if that means closing down its China offices.
The latest hacking attack also targeted another Chinese rights group named Civil Rights and Livelihood Watch; two news sites run by Chinese activists, Canyu and New Century News; and the Independent Chinese Pen Center, which posts essays by dissident writers, according to the e-mailed statement. Public records show the Web sites all share two neighboring IP (Internet Protocol) addresses, suggesting the sites were all affected by the DDoS attack.
The bandwidth consumed by the attack hit 2GB per second at its peak, the statement said, citing the Internet service provider for the Web sites.
The targeted IP addresses belong to The Planet, a server hosting provider based in Texas. No one at The Planet was immediately available to comment.
Hackers also placed malware on two of the Web sites before the attack, but that is now being removed, the statement said. The group that sent out the statement has often been hit by cyberattacks, sometimes leaving its Web site down for days, it said.
An advocacy group for foreign journalists in China last week said the Gmail accounts of at least two reporters there had been recently hijacked.