Chinese cyber security watchdogs warned computer users yesterday to arm themselves against an attack by a new Internet worm that could rival the devastating fury of the Blaster and Mydoom bugs, which infected millions of computers worldwide a couple of years ago.

Dubbed Dasher, the new worm has already started to hit computers in China, its sole target so far. Authorities said the number of infections was small as of yesterday, but the potential exists for massive damage.

Dasher exploits a vulnerability in Windows operating systems from Windows 2000 on up.

It can take complete control of an infected computer, view, change or delete data and create new accounts with full user rights, according to a Microsoft security bulletin.

Security authorities say the worm can even steal passwords to online bank accounts.

Infections can occur even if a computer user doesn't open an e-mail attachment, visit a Website or chat on MSN. Unprotected computers are vulnerable as soon as they're connected to the Internet. Once they're infected, host computers generate further attacks against other computers and may run slower than normal.

China's National Computer Virus Emergency Response Center confirmed yesterday that it has received reports of the worm and has informed big government and business enterprises and published a warning on its Website.

Up to yesterday, the computer worm had attacked only computers in China, according to Beijing Jiangmin Science Co, an anti-virus firm.

To protect against the worm, computer users are advised to download a patch from the Microsoft Website.

(Shanghai Daily December 20, 2005)