Linux Malware On The Rise

Assuming you’re safe from viruses and other malware just because you are on a non-Windows platform is a big mistake, as the number of Linux-based malware doubled in 2005, and Mac OS X is next to get hit, according to a report from Kaspersky Labs.

In a report titled “2005: *nix Malware Evolution,” the Russian antivirus software developer pointed out that the number of Linux-based malicious programs — viruses, Trojans, back-doors, exploits, and whatnot — doubled from 422 to 863.

Numerically, that pales compared to the 11,000 Kaspersky found for Windows in the second half of 2005 alone.

However, it could be more devastating because many non-Windows users assume malware is only a Windows problem and don’t take any precautions. Kaspersky said Linux users are careful, but one security expert disagrees.

“With Linux users, there’s a very vigilant effort to make sure the system is as secure as possible, mostly because Linux people are very aware of security dangers and the security that needs to be put in place,” said Shane Coursen, senior technical consultant with Kaspersky’s U.S. office in Woburn, Mass.

“The other thing is that there are people who have transitioned from Windows to Linux, thinking Linux would provide them more security, and they make sure their new Linux system is secured,” he added.

But Tom Ferris, researcher with Security Protocols, a computer security research firm in Mission Viejo, Calif., said the opposite.

“In people’s minds, if it’s non-Windows, it’s secure, and that’s not the case,” he said. “They think nobody writes malware for Linux or OS X. But that’s not necessarily true, as that report showed.”

The growth in Linux malware is simply due to its increasing popularity, particularly as a desktop operating system, said Coursen.

“The use of an operating system is directly correlated to the interest by the malware writers to develop malware for that OS,” he added.

The Kaspersky report said that the Unix picture mirrors that on the Win32 front. The biggest problems are exploits and back doors designed to steal information.

There are also sniffers, flooders and other hack tools. While rootkits get all the headlines, Coursen said the biggest problems will still be exploits and Trojans.

“Backdoors and Trojans are the most common as the major malware across all platforms because they give a hacker greater access to the system,” said Coursen. “That’s why they invest the most time in creating those. The reasons for wanting to get in aren’t different between Windows and Linux. They want to copy keystrokes for login information, passwords, credit-card transactions, and so on.”

Kaspersky thinks the Mac OS X platform is next to get hit. It’s growing in popularity, is based on FreeBSD, which has a few existing viruses, and there are more than a few holes in the operating system and in the Safari Web browser.

Ferris has been digging into OS X and posting numerous bugs to the Security Protocols Web site in recent weeks.

Get the Free Newsletter!

Subscribe to our newsletter.

Subscribe to Daily Tech Insider for top news, trends & analysis

News Around the Web