Hackers have begun using compromised servers instead of client PCs to launch more powerful denial of service attacks.
Hundreds of web servers are infected with a DoS application that transforms them into zombie drones, according to database security firm Imperva. These zombie servers are controlled using a simple web application, consisting of just 90 lines of PHP code.
Servers are harder to compromise than desktop PCs, which can potentially be compromised as easily as tricking a user into opening a maliciously constructed email or visiting a dodgy website. However once compromised servers offer more horsepower and, typically, fatter pipes for throwing out spurious traffic.
Attacks launched from web servers may also be more difficult to detect. "Trace backs typically lead to a lone server at a random hosting company," Imperva warns.
Amichai Shulman, Imperva's CTO, claims denial of service attacks from compromised servers are ongoing. "Now that a network of server bots has been created, it will be quite easy for them to 'rent' them out or increase their activity," he said.
"Companies should regularly monitor their Google presence to look for evidence of being compromised." ®