SANS, Microsoft, the NIPC, CERT/CC and four other leading security
organizations released the following alert today (Sunday, January 29)
at 4 pm. EDT.
 

A Very Real and Present Threat to the Internet:  July 31 Deadline
For Action

Summary: The Code Red Worm and mutations of the worm pose a continued
and serious threat to Internet users.  Immediate action is required
to combat this threat. Users who have deployed software that is
vulnerable to the worm (Microsoft IIS Versions 4.0 and 5.0) must
install, if they have not done so already, a vital security patch.

How Big Is The Problem? On July 19, the Code Red worm infected more
than 250,000 systems in just 9 hours. The worm scans the Internet,
identifies vulnerable systems, and infects these systems by installing
itself. Each newly installed worm joins all the others causing
the rate of scanning to grow rapidly. This uncontrolled growth in
scanning directly decreases the speed of the Internet and can cause
sporadic but widespread outages among all types of systems. Code Red
is likely to start spreading again on July 31st, 2001 8:00 PM EDT and
has mutated so that it may be even more dangerous.  This spread has
the potential to disrupt business and personal use of the Internet
for applications such as electronic commerce, email and entertainment.

Who Must Act? Every organization or person who has Windows NT or
Windows 2000 systems AND the IIS web server software may be vulnerable.
IIS is installed automatically for many applications. If you are not
certain, follow the instructions attached to determine whether you
are running IIS 4.0 or 5.0.  If you are using Windows 95, Windows 98,
or Windows Me, there is no action that you need to take in response
to this alert.

What To Do If You Are Vulnerable?

a. To rid your machine of the current worm, reboot your computer.
b. To protect your system from re-infection: Install Microsoft's
patch for the Code Red vulnerability problem:
  Windows NT version 4.0:
http://www.microsoft.com/Downloads/Release.asp?ReleaseID=30833
 Windows 2000 Professional, Server and Advanced Server:
http://www.microsoft.com/Downloads/Release.asp?ReleaseID=30800

Step-by-step instructions for these actions are posted at
www.digitalisland.net/codered

Microsoft's description of the patch and its installation, and the
vulnerability it addresses is posted at:
http://www.microsoft.com/technet/treeview/default.asp?url=
/technet/security/bulletin/MS01-033.asp

Because of the importance of this threat, this alert is being made
jointly by:

Microsoft
The National Infrastructure Protection Center
Federal Computer Incident Response Center (FedCIRC)
Information Technology Association of America (ITAA)
CERT Coordination Center
SANS Institute
Internet Security Systems
Internet Security Alliance