Heap-based buffer overflow in Internet Explorer 8 on Microsoft Windows 7 allows remote attackers to discover the base address of a Windows .dll file, and possibly have unspecified other impact, via unknown vectors, as demonstrated by Peter Vreugdenhil during a Pwn2Own competition at CanSecWest 2010.
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.