User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists due to a faulty allocation routine within the TextXtra.x32 module. This allocator allocates a buffer on the heap based on arithmetic involving a number of elements and a size of an individual element. As the fields come from the file, if either of them are large enough, the value used for the number of bytes to allocate can be made to overflow. As the return value is rarely checked any caller of this function can usually be made to overflow the returned buffer with user-supplied data. An attacker can leverage this to execute remote code under the context of the user running the browser.
Adobe has issued an update to correct this vulnerability. More details can be found at: