Microsoft on April 3 released a high-priority software patch intended to fix a dangerous vulnerability in its Vista and Windows operating systems.
The world's largest computer software company made the patch available as hacker groups, most of them based in China, intensified attacks crafted to exploit the weakness that Microsoft disclosed on April 5.
The vulnerability was found in Windows and Vista "ani" files that change cursors to hourglasses, animals or animated figures while computers are executing programs, according to Finland-based computer security firm F-Secure.