Malicious Worm Dasher Targets Windows

Just in time for the holidays, a worm called Dasher has hit the Internet, primarily targeting Windows 2000 systems. Dasher is one of three new attacks that have emerged in the past 24 hours targeting Microsoft Corp.’s software, according to Computerworld.

Dasher apparently exploits a recently patched bug in Microsoft Distributed Transaction Coordinator, a component of the operating system that is commonly used by database software to help manage transactions. Microsoft rates the bug “critical” for Windows 2000 systems. The worm’s emergence doesn’t come as a surprise. The proof-of-concept code that could be used to make a worm like Dasher first began circulating after Microsoft issued its patch in early October.

However, security researchers don’t think the worm will be as widespread as the Zotob attack, which brought down hundreds of thousands of systems worldwide last August.

Two variants of Dasher are now in circulation. Both versions install software that then tries to infect other vulnerable systems and can also be used to log keystrokes and turn the computer into a remotely controlled “bot” system.

–Alison Bass