CVE-2007-2583: MySQL Bugs: #27513: mysql 5.0.x + NULL pointer DoS

The in_decimal::set function in item_cmpfunc.cc in MySQL before 5.0.40, and 5.1 before 5.1.18-beta, allows context-dependent attackers to cause a denial of service (crash) via a crafted IF clause that results in a divide-by-zero error and a NULL pointer dereference.