Tools designed for testing server and network defences are being snapped up by hacktivists to launch denial-of-service attacks on websites.
More and more assaults are concentrating on knackering web apps and the HTTP server software running it, rather than simply flooding the underlying stack with bogus traffic to exhaust resources and bandwidth, according to the latest edition of Imperva's Hacker Intelligence report.
This type of attack may be directed at specific flavours of web servers such as IIS or Apache, or to specific applications, such as SharePoint - Microsoft's content management server software.
The latest and most popular distributed denial-of-service (DDoS) tools include LOIC, SlowHTTPTest and railgun. The use of the latter two white-hat tools shows how black-hat hackers have begun running attacks that utilise white-hat testing tools. Attacks analysed by Imperva in its report include network assaults by hacktivists in Bahrain, Colombia and Russia as well as web blitzes against businesses linked to DDoS-for-hire scams. DDoS attacks typically run from botnet networks of compromised computers.
In many cases the distinct signature of each weapon can be used to devise effective filtering rules.
"Denial-of-service is a primitive, yet popular attack vector, for politically and profit-motivated hackers," said Tal Be’ery, a senior web researcher at Imperva. "DDoS can gridlock enterprise resources to a halt, just like traffic on the highway, but organisations can mitigate these effects by learning how to identify and protect against malicious traffic." ®