At first blush, the past two weeks have not been good for the image of Apple's Mac OS X: Public descriptions of two worms and a trivial exploit for a serious software issue in the operating system appeared on the internet.
However, the three programs are hardly a threat to systems running Mac OS X, according to security professionals.
One worm, known as OSX.Leap.A and assigned CME-4 by the Common Malware Enumeration Project, requires too much user interaction, hobbling its attempts to spread. A second worm, dubbed InqTana, and its two variants are actually proof-of-concept programs that were not discovered on the internet but were instead sent to anti-virus vendors and Apple by a researcher to prove that worms can spread through Bluetooth. And while the release of code for a vulnerability that could be exploited through Safari and Mail is a bit more serious, no incidents of websites exploiting the flaw have yet been reported.
"I don't think what we've seen is serious at all from the end-user perspective," said Mikael Albrecht, product manager with anti-virus firm F-Secure. He added that the issues the programs use to attempt to spread could result in more serious attacks, however. "From the security perspective, the vulnerabilities are quite severe."
The largely ineffectual attacks add fuel to the fiery debate over the security of Apple's operating system. Many Mac users believe they are better protected than the average Windows user against malicious attacks. Most security professionals argue that, as flaw finders scrutinise the increasingly popular operating system, more vulnerabilities will be found, and Mac users will have to deal with many of the threats that worry Windows users.
In the latest security issue for Mac OS X, a vulnerability in how the operating system uses meta data to associate file types with programs could be exploited to allow a Mac to be compromised through web browsing or via an email message, according to flaw finder Michael Lehn, a graduate student and researcher in the University of Ulm's Department of Numerical Analysis. The researcher recently discovered the vulnerability and reported it to Apple.
Because of the severity of the flaw, and the possibility that someone else had found it - Apple lists the flaw as a duplicate in its bug database - Lehn opted to release details of the vulnerability and proof-of-concept code, a move he said helps Mac users. However, the move violates generally accepted responsible disclosure guidelines.
"Because of the first worm, too many people were suddenly starting to think about and investigate the possibility of writing a Mac OS X worm," Lehn said. "Publishing the exploit as fast as possible is the best for all Apple users. I think at the end of the week, every Apple user will know about it."
Without advanced notification, Apple is currently scrambling to release a patch for the issue, which has not yet been encountered by users on the internet.
"Apple takes security very seriously," an Apple spokesperson told SecurityFocus. "We're working on a fix so that this doesn't become something that could affect customers."
The company added that Mac users should only accept files from the software developers and websites that they know and trust.