On Sun, 26 Jan 2003, Chris Lloyd wrote:
Just a point here: Many road warriors are work-at-home folks who have their computers on 24x7. They may be infected, and will fire up their VPN tunnels Monday morning. This may introduce the worm into the chewy center of many corporate networks. Hopefully folks have put the proper filters in place on their VPN access points.
Personally, I think it's unlikely the situation will get worse on Monday because of people starting work. The first reason is that you can only get infected if you're running SQL server (or MSDE) at home and someone sends you one of the special packets. The second reason is that you, if you're infected, send the packets to random IP addresses, and not only do you have to randomly choose an address on the corporate LAN, but it has to be a machine running SQL server. To my mind the probability of all these things being the case is microscopic!
The worm prefers addresses "close to home" and sends out tens of thousands of packets per second. Depending on the preference for local addresses a single infected host could infect an entire /16 in a few seconds, and a /8 in less than an hour. The entire internet takes less than a week if the random address generator doesn't re-hit the same addresses. One interesting aspect of this worm is that it seems capable of passing through all kinds of barriers. After two infected machines were cleaned up and filters were in place, I still saw one or two copies of the worm coming in addressed to the subnet broadcast addresses on interfaces facing the local network. Finding out how exactly the worm (ab)used broadcast and multicast addresses is going to be fertile ground for research.