Be on guard against multi-layer threats

Malware are increasingly becoming complex threats designed with multiple components that target different enterprise weaknesses, say industry watchers.

In other words, the next security threat that hits your organization could be a keylogger, Trojan, and 'bot' rolled into one.

The first component will trigger off "a chain of other components that seek to stealthily accomplish" the intended purpose, according to Arun Chandrasekaran, industry manager for ICT practice at consulting firm Frost & Sullivan.

Jens Andreassen, vice president for the Asia-Pacific at Fortinet, told ZDNet Asia in an e-mail that multi-component threats have existed for several years, but more than ever, today's blended threats have many more components or functionalities "to maximize the opportunity for a successful attack".

"As security products add multiple layers of defense, cyber criminals are matching this with a multi-component offense approach. Multi-component threats are…becoming more sophisticated and adding more and more components for a snowball effect," said Andreassen, adding that malware writers are also tapping on "higher profile vehicles such as blogs and social networking sites".

According to Paul Ducklin, head of technology for the Asia-Pacific region at Sophos, the Web has aided the rise of multi-component threats.

"Most modern malware involve a series of attack stages, relying on and using a number of parts," he explained in an e-mail. "With the Internet, it is no longer necessary for the malware to carry around all the pieces it needs in a single file or on a single disk--additional parts can be easily downloaded when needed."

According to Ducklin, security vendors face both challenges and opportunities in dealing with multi-component threats. "The most obvious challenge is that when we see one part of a multi-component threat, we don't automatically know where this component fits in to the entire attack.

"For example, we might receive an exploit which downloads a piece of malware from a URL which is not yet active. So although we can now proactively block any future downloads, we can't yet say what risk the link poses to an unprotected computer," he added.

On the other hand, there are more avenues to counter the threat--attacks can be thwarted by blocking any one of the components involved, noted Ducklin.

He said: "Such attacks have all the weaknesses of an electrical circuit…cut a wire anywhere and the whole thing goes dead, compared to the strengths of a parallel circuit, in which each component has to be isolated separately."

Businesses, said Ducklin, run into the danger of having their corporate Web sites used as "a staging post" for malware attacks. According to him, about 80 percent of all infected Web pages are on compromised legitimate sites.

Suffering a Web site attack not only damages the company's reputation by highlighting the fact that there is a security problem, it is also time-consuming and costly to repair, Ducklin pointed out. In addition, legitimate visitors may no longer be able to use the site effectively, and end up visiting a competitor's site instead.

Frost & Sullivan's Chandrasekaran added that "due to the stealthy nature, many users might not detect any abnormality in their system behavior and performance". Businesses, therefore, need to have a "defense-in-depth approach to security" and educate employees on security hazards in a timely manner, he said.