After years of writing viruses and worms for operating systems and software running on Internet servers, hackers found some new areas to target in 2005, according to a report on security trends published Tuesday.
 
Over the past year, attackers have switched their focus to network devices and applications, specifically back-up software and even the security software designed to protect computers, according to the 2005 SANS Top 20 list of the most critical Internet security vulnerabilities, says Alan Paller, director of research with the SANS Institute, a training organization for computer security professionals.

“There has been a 90-degree turn in the way attackers are coming after you,” Paller says. Most organizations have adopted means to automatically patch vulnerabilities in operating systems, he says, but not in applications. “Those applications don’t have automated patching, so we’re back to the Stone Age.”

And by exploiting flaws in networking gear, hackers are finding their way onto corporate networks.

"Other, more sophisticated attackers, looking for new targets, found they could use vulnerabilities in network devices to set up listening posts where they could collect critical information that would get them into the sites they wanted," he added.

This new focus on client applications and networking products has happened because so many server-side and operating system bugs have been fixed, says Gerhard Eschelbeck, CTO and vice president of engineering with Qualys, and a contributor to this year's list. "A lot of the low-hanging fruit has been identified now," he says. "We really reached a tipping point earlier this year, where people started to look aggressively at client-side applications."

Security researchers also started looking at vulnerabilities in networking products, thanks in part to a controversial presentation by security researcher Michael Lynn at this year's Black Hat 2005 conference in Las Vegas. Cisco sued Lynn after he discussed security problems in the Internetwork Operating System (IOS) software that is used by Cisco's routers.

This is the first year that networking products have appeared on the SANS list, with Cisco vulnerabilities taking three of the 20 slots. The list also includes nine common application vulnerabilities, two Unix problems and six Windows issues, all of which "deserve immediate attention from security professionals," according to SANS.

The IDG News Service is a Network World affiliate.