נחשפה פרצת אבטחה חמורה באינטרנט אקספלורר

The Details

The exploit leverages a previously unknown use-after-free vulnerability, and uses a well-known Flash exploitation technique to achieve arbitrary memory access and bypass Windows' ASLR and DEP protections.

Exploitation

• Preparing the heap

The exploit page loads a Flash SWF file to manipulate the heap layout with the common technique heap feng shui. It allocates Flash vector objects to spray memory and cover address 0×18184000. Next, it allocates a vector object that contains a flash.Media.Sound() object, which it later corrupts to pivot control to its ROP chain.

• Arbitrary memory access

The SWF file calls back to in IE to trigger the IE bug and overwrite the length field of a Flash vector object in the heapspray. The SWF file loops through the heapspray to find the corrupted vector object, and uses it to again modify the length of another vector object. This other corrupted vector object is then used for subsequent memory accesses, which it then uses to bypass ASLR and DEP.