Multiple buffer overflows in the Resolution Service for Microsoft SQL Server 2000 and Microsoft Desktop Engine 2000 (MSDE) allow remote attackers to cause a denial of service or execute arbitrary code via UDP packets to port 1434 in which (1) a 0x04 byte that causes the SQL Monitor thread to generate a long registry key name, or (2) a 0x08 byte with a long string causes heap corruption, as exploited by the Slammer/Sapphire worm.