The Just In Time (JIT) Compiler service in Microsoft .NET Framework 1.0, 1.1, and 2.0 for Windows 2000, XP, Server 2003, and Vista allows user-assisted remote attackers to execute arbitrary code via unspecified vectors involving an "unchecked buffer," probably a buffer overflow, aka ".NET JIT Compiler Vulnerability".
Improper Restriction of Operations within the Bounds of a Memory Buffer The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary.