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Act now to stop Web meltdown

CW360 reporters
Monday 30 July 2001 03:04
Network managers have until midnight to avoid a possible Internet meltdown before the Code Red worm strikes at midnight Greenwich Mean Time on 1 August.

Microsoft and number of high-level US IT security bodies today issued a last-ditch warning, urging users of Microsoft's Internet Information Server to protect themselves.

The only guaranteed defence against the worm, which can cause denial of service attacks that bring Internet traffic to a halt, is to install patches that close the security holes targeted by the worm.

Microsoft warned that the worm could give a hacker "complete control of the server and allow him to take any desired action on it."

Eric Chien, chief researcher at Symantec's anti virus research centre said, "Most large corporations have installed this patch already. Those that haven't will be small businesses and they simply don't know about it or realise that they are at risk."

However, unprotected machines could become hosts in which the worm replicates. If sufficient copies of the worm are loose the Internet will grind to a halt, as it did with the Melissa virus, putting global e-commerce revenues at risk.

"Every organisation or person who has Windows NT or Windows2000 systems AND the IIS web server software may be vulnerable," according to the CERT coordination centre, the world's leading, independent security body.

The Code Red worm takes advantage of a buffer overflow vulnerability, allowing the attacker to gain control over an unprotected server. Most system administrators and users will not even know they have been compromised.

A buffer overflow occurs when an application fails as a result of being sent too much data. Good programming should prevent such occurrences.

The Microsoft patch effectively disables a feature called script mapping on Index Server, when it is being used in conjunction with the IIS Web server.

Graham Cluley, senior technology consultant at Sophos Anti Virus urged users to "apply the patch from Microsoft. They released it on 18 June and mind bogglingly enough, people still haven't applied it," he said

Cluley also said IT managers had a duty to ensure the worm did not spread, "Don't just apply this patch to protect your own computers, but as part of the Internet community, we should all be doing our bit clearing up the Net."

Marty Lindner of CERT said, "As long as there is at least one machine out there still scanning and spreading the worm, it will find a vulnerability again and continue."

The severity of the threat resulted in a joint call to arms from Microsoft, the National Infrastructure Protection Centre, the Federal Computer Incident Response Centre (FedCIRC), the Information Technology Association of America (ITAA), the CERT Coordination Centre, the SANS Institute, Internet Security Systems and the Internet Security Alliance

Who is affected?
Every organisation or person who has Windows NT or Windows2000 systems and the IIS web server software may be vulnerable.

IIS is installed automatically for many applications. If you are not certain, follow the "Step by Step" instructions from Digital Island 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
1.
To rid your machine of the current worm, reboot your computer.

2. To protect your system from re-infection: Install Microsoft's patch for the Code Red vulnerability problem:

Windows NT version 4.0
www.microsoft.com/Downloads/Release.asp?ReleaseID=30833

Windows 2000 Professional, Server and Advanced Server
www.microsoft.com/Downloads/Release.asp?ReleaseID=30800

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

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