Exploit Code Published for Apple OS X Glitch

Researchers have published exploit code that targets an unpatched kernel vulnerability in Apple’s OS X desktop software.

An independent vulnerability analyst working as part of the “Month of Kernel Bugs” campaign released the details necessary to attack the hole in OS X on Nov. 22, revealing the manner in which hackers could target the glitch, which affects the way Apple’s software handles disk image files.

The researcher, identified only by the screen name “LMH,” issued the exploit via a post on the Kernel Fun Web site.

“Mac OS X fails to properly handle corrupted image structures, leading to an exploitable denial of service condition,” LMH wrote in his latest blog.

“Although it hasn’t been checked further, memory corruption is present under certain conditions.”

The researcher said that the demonstration exploit offered on the site would be unlikely to allow arbitrary code execution if applied by attackers, however, the analyst indicated that the flaw could be taken advantage of by malware writers by targeting the manner in which Cupertino, Calif.-based Apple’s Safari browser downloads online image files.

Apple representatives didn’t immediately return calls seeking comment on the exploit.

Security researchers at Secunia rated the exploit as “highly critical,” the software company’s second most severe threat ranking, and said the attack could be used by local users to gain escalated privileges and utilized by malware writers to compromise a vulnerable system.

The Copenhagen, Denmark-based firm specifically said that the vulnerability is caused due to an error in the OS X AppleDiskImageController when the system is handling corrupted image files and can be exploited to cause a memory corruption.

Such an attack could lead to execution of arbitrary code in kernel-mode, Secunia said in a post to its Web site.

Click here to read more about “Apple-protected binaries.”

Starting on Nov. 1, a loosely federated collection of independent security researchers launched the Month of Kernel Bugs project in an effort to bring attention to known vulnerabilities in operating system kernels. The group plans to release one new exploit aimed at an unpatched flaw in an OS kernel for each day during the month.

The first exploits released by the group targeted another Apple flaw existing in the wireless drivers of its PowerBook notebook computers, while other exploits introduced by the group have highlighted issues in Microsoft Windows and Linux-based software.

In a report released earlier his month, researchers at antivirus market leader Symantec highlighted the growing number of vulnerabilities being discovered in Apple’s software, which has long avoided the same volume of attacks aimed at Microsoft’s Windows OS.

Symantec researchers said that vulnerabilities discovered in Apple software typically allow for local privilege escalation, client-side code execution, and remote code execution.

While the company said that exploiting the vulnerabilities in OS X is “not notably more or less difficult” than doing so on most other platforms, hackers have yet to target the Apple flaws as aggressively as they have pursued similar issues in Microsoft products.

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