Denial-of-service attacks becoming more sophisticated

Agencies and companies are used to dealing with attempts to knock their websites offline.

But a shift in the character of distributed denial-of-service (DDoS) attacks is creating new challenges, according to a quarterly threat report by Massachusetts-based Corero Network Security.


Hackers are launching shorter DDoS attacks that can help disguise more dangerous cyber intrusions taking place at the same time, the company found.

To do this, hackers distract IT personnel by flooding systems with traffic while leaving just enough bandwidth open to initiate attacks aimed at gathering sensitive data.

Often, Corero found, the campaigns are so short that security teams might miss them: 73 percent of DDoS attacks on customers lasted less than five minutes, while 96 percent lasted less than 30 minutes.

“These findings highlight a new trend in DDoS attack activity: short bursts of damaging attack traffic versus prolonged events,” the report stated.

Analysts sought to distinguish between the best-known type of DDoS attack – based purely on false traffic — and the new, more dangerous types of DDoS intrusions.

“Attackers have implemented more adaptive multi-vector methods to profile the nature of the target network’s security defenses, and subsequently selected a second or third attack designed to circumvent an organization’s layered protection strategy, the report continued.

“While volumetric attacks remain the most common DDoS attack type targeting Corero customers, combination or adaptive attacks are emerging as a new threat vector.”

The average cost of a DDoS outage is $720,000, or $8,000 per minute of network downtime, Corero found.