Mac OS X security myth exposed

Windows is more secure than you think, and Mac OS X is worse than you ever imagined. That is according to statistics published for the first time this week by Danish security firm Secunia.

The stats, based on a database of security advisories for more than 3,500 products during 2003 and 2004 sheds light on the real security of enterprise applications and operating systems, according to the firm. Each product is broken down into pie charts demonstrating how many, what type and how significant security holes have been in each.

One thing the hard figures have shown is that OS X's reputation as a relatively secure operating system is unwarranted, Secunia said. This year and last year Secunia tallied 36 advisories on security issues with the software, many of them allowing attackers to remotely take over the system - comparable to figures on operating systems such as Windows XP Professional and Red Hat Enterprise Server.

"Secunia is now displaying security statistics that will open many eyes, and for some it might be very disturbing news," said Secunia chief executive Niels Henrik Rasmussen. "The myth that Mac OS X is secure, for example, has been exposed."

Its new service, easily acessible on its website, allows enterprises to gather exact information on specific products, by collating advisories from a large number of third-party security firms. A few other organisations maintain comparable lists, including the Open Source Vulnerability Database (OSVDB) and the Common Vulnerabilities and Exposures (CVE) database, which provides common names for publicly known vulnerabilities.

Secunia said the new service could help companies keep an eye on the overall security of particular software - something that is often lost in the flood of advisories and the attendant hype. "Seen over a long period of time,the statistics may indicate whether a vendor has improved the quality of their products," said Secunia CTO Thomas Kristensen. He said the data could help IT managers get an idea of what kind of vulnerabilities are being found in their products, and prioritise what they respond to.

For example, Windows security holes generally receive a lot of press because of the software's popularity, but the statistics show that Windows isn't the subject of significantly more advisories than other operating systems. Windows XP Professional saw 46 advisories in 2003-2004, with 48 percent of vulnerabilities allowing remote attacks and 46 percent enabling system access, Secunia said.

Suse Linux Enterprise Server (SLES) 8 had 48 advisories in the same period, with 58 percent of the holes exploitable remotely and 37 percent enabling system access. Red Hat's Advanced Server 3 had 50 advisories in the same period - despite the fact that counting only began in November of last year. Sixty-six percent of the vulnerabilities were remotely exploitable, with 25 granting system access.

Mac OS X doesn't stand out as particularly more secure than the competition, according to Secunia. Of the 36 advisories issued in 2003-2004, 61 percent could be exploited across the Internet and 32 percent enabled attackers to take over the system. The proportion of critical bugs was also comparable with other software: 33 percent of the OS X vulnerabilities were "highly" or "extremely" critical by Secunia's reckoning, compared with 30 percent for XP Professional and 27 percent for SLES 8 and just 12 percent for Advanced Server 3. OS X had the highest proportion of "extremely critical" bugs at 19 percent.

As for the old guard, Sun's Solaris 9 saw its share of problems, with 60 advisories in 2003-2004, 20 percent of which were "highly" or "extremely" critical, Secunia said.

Comparing product security is notoriously difficult, and has become a contentious issue recently with vendors using security as a selling point. A recent Forrester study comparing Windows and Linux vendor response times on security flaws was heavily criticised for its conclusion that Linux vendors took longer to release patches. Linux vendors attach more weight to more critical flaws, leaving unimportant bugs for later patching, something the study failed to factor in, according to Linux companies. Vendors also took issue with the study's method of ranking "critical" security bugs, which didn't agree with the vendors' own criteria.

Secunia agreed that straightforward comparisons aren't possible, partly because some products receive more scrutiny than others. Microsoft products are researched more because of their wide use, while open-source products are easier to analyse because researchers have general access to the source code, Kristensen said.

"A third factor is that Linux / Unix people are very concerned about privilege escalation vulnerabilities, while Windows people in general are not, especially because of the shatter-like attacks which have been known for six years or more," he said. "A product is not necessarily more secure because fewer vulnerabilities are discovered."