Apple Mac OS X Suffers Vulnerability
Researchers have designed exploit code that attacks unpatched 'kernel' vulnerabilityin Apple's OS X desktop program. A vulnerability analyst working independently on the "Month of Kernel Bugs" campaign described the details on November 22 2006 required to attack the flaw in OS X. He explained the manner which hackers could use to exploit the flaw that affects Apple software's operation on disk image files.
The researcher, who calls himself only by "LMH", released the code through a post on the 'Kernel Fun Website'.
As Mac OS X com.apple.AppleDiskImageController is unable to adequately handle corrupt DMG images, it leads to memory corruption exploitable by 'kernel-mode arbitrary' code executed by disadvantaged users.
The flaw is remotely exploitable when 'Safari' browser installs DMG (Disk image) files via a visit to an URL. However, prevention requires modifying the 'Preferences' and disabling the function of 'opening safe files' after downloading.
Online criminals target to compromise Macs with such vulnerability by tricking surfers to browse websites containing corrupt DMG files. Several 'OS X binaries' take the form of DMG files that are complete in itself and become 'auto-mounted' in a default configuration, notes SANS Institute's Internet Storm Center.
Security firm Secunia has labeled the exploit as "highly critical", which is Apple's second most dangerous threat. Local users could use the attack to gain unauthorized access to private information or malware authors could use it to compromise flawed systems.
Experts advise that prevention of the flaw is possible by disabling 'safe files' after downloading, a setting adjustable in 'Safari Preferences'.
This nascent flaw continues from a problem that arose in 2005 with Mac OS X v 10.4's 'Dashboard technology'. After a download 'Safari 2.0' would automatically open safe files and a programmer showed how to randomly install 'Dashboard widgets' in that way. A similar problem was found this year relating to 'shell script execution' from a Web page. The remedy to both the problems is to turn off 'open safe files' after download.
Related article: Apple Patches QuickTime 13 Month Old Flaw
» SPAMfighter News - 27-11-2006