Within three days of Apple’s release of the Safari Web browser for Windows XP and Vista in beta testing versions, several significant security flaws were discovered, some of which were reported to Apple. The company responded quickly, issuing a bug fix release last week for three potential problems that involved specially crafted content at malicious Web sites that must be visited to trigger the vulnerabilities.
The bugs were discovered – at least in the descriptions provided by the coders who found them – through the use of fuzzing, a technique that throws piles of crud at targeted areas of a system or application to see what breaks. Fuzzing is a brute force method, but it has to be paired with more refined technical knowledge to understand how to take advantage of a flaw.
A non-programmer could potentially use fuzzing to figure out how to crash a piece of software or even an operating system, but they used to have a harder time making use of that crash to tailor an attack that would allow them some sort of access. Programs like Metasploit provide a bridge between fuzzing and exploitation, however, and as they become increasingly powerful, “script kiddies” – relatively unsophisticated users who use prefabricated attacks – may have more disruptive power.
It’s disturbing that Apple isn’t stress-testing its public beta software with the same kind of readily available tools for fuzzing used by both researchers and the nefarious. Many of the Month of Apple Bugs flaws (see “MoAB Is My Washpot,” 2007-02-19), as well as many recent AirPort and AirPort Extreme problems, were discovered through fuzzing.
Apple’s security update notice, which I cannot find archived online, notes, “This beta software is for trial purposes and intended to gather feedback prior to a full release.” That is, “Bite us: This is beta software.” The flip side, of course, is when Steve Jobs says, hey, go download the beta, it’s hard to argue that serious security flaws aren’t just as serious as they are in released software.
Apple also said, “As with all our products, we encourage security researchers to report issues to [email protected]” No researchers were credited for the three fixed bugs.