Techies at Microsoft Corp. have been working double time this week trying to make sure that
customers can still get to needed software patches despite the coming of the Blaster worm’s
Distributed Denial-of-Service (DDoS) attack.
The attack, which is expected to start tonight, is aimed at Microsoft’s windowsupdate.com
Web site — the site users have been sent to for the patch that will ward off the Blaster
worm. Microsoft execs want to make sure that system patching continues even after the attack
”we’ve been working nonstop to make sure we can provide the patch to our customers and we
think we’ll be able to,” says Stephen Toulouse, a security program manager in Microsoft’s
Security Response Center. ”Our number one concern is getting customers the patch and making
sure they can get to our site.”
To that end, Toulouse says Microsoft is guiding users to the patch through an alternate
route. Customers can get to it by going to www.microsoft.com/security. That site won’t be
affected even if the windowsupdate.com site goes offline during an attack.
Toulouse adds that they’ve taken steps to ward off the attack and keep the site up and
running, but he would not give specifics for fear that the information would help future
He adds that even though Microsoft is frequently the target of DDoS attacks and has practice
guarding against them, he can’t be sure the site won’t experience problems once the Blaster
attack hits full force.
”Denial-of-Service attacks tend to be successful because they’re brute force attacks,”
says Toulouse. ”It’s always one of those things where we’ll know when it happens.”
Microsoft has logged an increase in traffic to the windowsupdate.com site over the past
several hours, Toulouse says, adding that some customers had their computer clocks
misconfigured so their DoS attacks came early. But he expects to see the traffic flow to the
site increase steadily over the course of the day today and tomorrow.
”We’ve just been preparing as if it’s going to start any moment,” says Toulouse.
The Blaster worm was first detected on Monday. It quickly spread from machine to machine
across the globe through a flaw in the Windows operating system. But the worm doesn’t carry
a destructive payload, only causing a small percentage of infected computers to reboot
because of a flaw in its own coding.
Instead, Blaster, otherwise known as LovSan and Poza, is specifically aimed at causing
trouble for Microsoft. The worm is geared to harvest as many vulnerable systems as possible
and launch a DDoS attack on the windowsupdate.com Web site starting late Friday or early
Saturday morning. By focusing all the net congestion on that Web site, the author of the
worm is deliberately trying to make it difficult for IT managers and individual users to
download the patch they need to secure their systems against the worm.
Several anti-virus and security companies, including Symantec Corp., raised the worm’s
threat level to their second-highest rating earlier this week, despite the fact that the
number of new infections had leveled off or even slowed. Blaster has not caused much network
congestion and hasn’t affected Internet traffic on anything but a very localized scale.
But analysts say it’s the potential they’re worried about.
Blaster exploits a flaw with the Remote Procedure Call (RPC) process, which controls
activities such as file sharing. The flaw enables the attacker to gain full access to the
system. The vulnerability itself, which affects Windows NT, Windows 2000, Windows 2003 and
Windows XP machines, affects both servers and desktops, expanding the reach of any exploit
that takes advantage of it.
Where the vulnerability affects servers and desktops in such popular operating systems,
there are potentially millions of vulnerable computers out there right now. The security
industry sent out a widespread warning about two weeks ago, spurring many companies to
install the necessary patch, which was available from Microsoft almost a month ago.
And with millions of systems still unpatched, Microsoft is determined to make sure customers
are able to get onto their Web site and download the needed fix.