A botnet has been systematically attacking Web sites that post blogs or forums containing content critical of the Vietnamese Communist Party. The botnet, thought to include about 15,000 bots, is launching massive denial-of-service (DOS) attacks to make the content unavailable, according to security firm SecureWorks.
"These are definitely political attacks against people exercising freedom of speech," says Joe Stewart, SecureWorks' director of malware research. There are indications that the current distributed DoS attacks against Vietnamese anti-communist bloggers appear to perpetrated by a pro-communist hacking group that's taking credit for the attacks, he says.
Dubbed Vecebot, the botnet's DoS attacks against the anti-communist blogs are being carried out by manipulating compromised PCs mainly in Vietnam. Because some of the blog sites and forums are located on sites outside Vietnam, such as Opera.com in Norway, there have been disruptions far beyond Vietnam.
DDoS attacks and cyber intrusions against several of the same anti-communist blogging sites and forums occurred in January and February of this year by means of a different Trojan known as Vulcanbot, according to SecureWorks. The security firm notes the same perpetrators may be behind both the Vecebot and Vulcanbot attacks.