WebKit, as used in Apple iTunes before 10.2 on Windows, does not properly parse HTML elements associated with document namespaces, which allows man-in-the-middle attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via vectors related to a "dangling pointer" and iTunes Store browsing, a different vulnerability than other CVEs listed in APPLE-SA-2011-03-02-1.
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.