The Blaster worm (a.k.a. Lovsan or Lovesan) was a computer worm that spread on computers running the Microsoft operating systems, Windows XP and Windows 2000, during August 2003.

The worm was first noticed and started spreading in the wild on August 11. The rate that it spread increased until the number of infections peaked on August 13. Filtering by ISPs and wide spread publicity about the worm curbed the spread of Blaster.

The worm was programmed to start a SYN flood on August 15 against port 80 of windowsupdate.com, thereby creating a denial-of-service attack (DoS) against the site. The damage to Microsoft was minimal as the site targeted was windowsupdate.com instead of windowsupdate.microsoft.com to which it was redirected. Microsoft temporarily shut down the targeted site to minimize potential effects from the worm.

The worm spread by exploiting a buffer overflow in the DCOM RPC service on the affected operating systems.

The worm contains two messages hidden in strings. The first:

I just want to say LOVE YOU SAN!!

Is why the worm is sometimes called the Lovesan worm. The second:

billy gates why do you make this possible ? Stop making money 
and fix your software!!

is an apparent message to Bill Gates, the co-founder of Microsoft, and the target of the worm.

On August 29, 2003, Jeffrey Lee Parson, an 18-year-old from Hopkins, Minnesota was arrested for creating the B variant of the Blaster worm; he admitted responsibility and was sentenced to an 18-month prison term in January 2005.

Side effects

Although the worm can only spread on systems running Windows 2000 and Windows XP (32 bit) it can cause instability in the RPC service on systems running Windows NT, Windows XP (64 bit), and Windows Server 2003. This can even lead to the system becoming so unstable that it displays the following message and then restarts:

Windows must now restart because the Remote Procedure Call 
(RPC) Service terminated unexpectedly.

This error message and the Windows restart can be avoided by changing the properties of the Remote Procedure Call (RPC) service, buying an infected user enough time to remove the virus from their system and install a patch removing the vulnerability.

Another method to stop the computing from restarting can be had thus:

• Go to Start->Run
• Type "shutdown -a" and press Enter

If ran as an Administrator, this will stop the reboot. (-a stands for "Abort")

Additionally, systems running the Open Software Foundation's Distributed computing environment can be affected by traffic generated from the worm. Packets generated by the worm can cause DCE to crash causing a Denial of Service of DCE.

See also

• Notable computer viruses and worms

External links

• Security Response site from Symantec