Buffer overflow in URLMON.DLL in Microsoft Internet Explorer 5.01 through 6 allows remote attackers to execute arbitrary code via a crafted URL with an International Domain Name (IDN) using double-byte character sets (DBCS), aka the "Double Byte Character Parsing Memory Corruption Vulnerability."
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.