Concept
Blaster (also known as Lovsan, Lovesan, or MSBlast) was a computer worm that spread on computers running operating systems Windows XP and Windows 2000 during August 2003. The worm was first noticed and started spreading on August 11, 2003. The rate that it spread increased until the number of infections peaked on August 13, 2003. Once a network (such as a company or university) was infected, it spread more quickly within the network because firewalls typically did not prevent internal machines from using a certain port. Filtering by ISPs and widespread publicity about the worm curbed the spread of Blaster. In September 2003, Jeffrey Lee Parson, an 18-year-old from Hopkins, Minnesota, was indicted for creating the B variant of the Blaster worm; he admitted responsibility and was sentenced to an 18-month prison term in January 2005. The author of the original A variant remains unknown. According to court papers, the original Blaster was created after security researchers from the Chinese group reverse engineered the original Microsoft patch that allowed for execution of the attack. The worm spreads by exploiting a buffer overflow discovered by the Polish security research group Last Stage of Delirium in the DCOM RPC service on the affected operating systems, for which a patch had been released one month earlier in MS03-026 and later in MS03-039. This allowed the worm to spread without users opening attachments simply by spamming itself to large numbers of random IP addresses. Four versions have been detected in the wild. These are the most well-known exploits of the original flaw in RPC, but there were in fact another 12 different vulnerabilities that did not see as much media attention. The worm was programmed to start a SYN flood against port 80 of windowsupdate.com if the system date is after August 15 and before December 31 and after the 15th day of other months, thereby creating a distributed denial of service attack (DDoS) against the site. The damage to Microsoft was minimal as the site targeted was windowsupdate.
