Buffer overflow in the Mach-O input file loader in Hex-Rays IDA Pro 5.7 and 6.0 allows user-assisted remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a crafted Macho-O file.
https://www.hex-rays.com/vulnfix.shtml
http://www.vupen.com/english/advisories/2011/0357