Червь Blaster: История и последствия заражения 2003 года

2003 Windows computer worm

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.

May 28, 2003: Microsoft releases a patch that would protect users from an exploit in WebDAV that Welchia used. (Welchia used the same exploit as MSBlast but had an additional method of propagation that was fixed in this patch. This method was only used after 200,000 RPC DCOM attacks the form that MSBlast used.) July 5, 2003: Timestamp for the patch that Microsoft releases on the 16th. Around July 16, 2003: White hat hackers create proof of concept code verifying that the unpatched systems are vulnerable. The code was not released. July 21, 2003: CERT/CC suggests also blocking ports 139 and 445. August 1, 2003: The U. S. issues an alert to be on the lookout for malware exploiting the RPC bug. August 11, 2003: Symantec Antivirus releases a rapid release protection update. August 15, 2003: The number of infected systems is reported at 423,000. August 16, 2003: DDoS attack against windowsupdate. com starts. (Largely unsuccessful because that URL is merely a redirect to the real site, windowsupdate. microsoft. com.) August 18, 2003: The related helpful worm, Welchia, appears on the internet. August 19, 2003: Symantec upgrades their risk assessment of Welchia to "high" (category 4). August 25, 2003: McAfee lowers their risk assessment to "Medium". August 27, 2003: A potential DDoS attack against HP is discovered in one variant of the worm. February 15, 2004: A variant of the related worm Welchia is discovered on the internet. February 26, 2004: Symantec lowers their risk assessment of the Welchia worm to "Low" (category 2).

Although the worm can only spread on systems running Windows 2000 or Windows XP, it can cause instability in the RPC service on systems running other versions of Windows NT, including Windows Server 2003 and Windows XP Professional x64 Edition. In particular, the worm does not spread in Windows Server 2003 because Windows Server 2003 was compiled with the /GS switch, which detected the buffer overflow and shut the RPCSS process down. When infection occurs, the buffer overflow causes the RPC service to crash, leading Windows to display the following message and then automatically reboot, usually after 60 seconds. This was the first indication many users had an infection; it often occurred a few minutes after every startup on compromised machines. A simple resolution to stop countdown is to run the "shutdown /a" command, causing some side effects such as an empty (without users) Welcome Screen. The Welchia worm had a similar effect. Months later, the Sasser worm surfaced, which caused a similar message to appear.