Telnetting to Port 53 May Crash DNS Service

ID: Q162927

The information in this article applies to:

Microsoft Windows NT Server version 4.0

SYMPTOMS

A Windows NT 4.0 Domain Name Service (DNS) server produces the following event error 454:

DNS Server select() Function failed. The data is the error.

Besides the event error, CPU usage is high, the DNS server is unstable, and it sometimes crashes.

CAUSE

The possible cause of this problem is when an unknown user telnets to the DNS server port 53. When this is done, and a few characters are typed, the above behavior is seen on the Windows NT 4.0 DNS server.

RESOLUTION

Obtain the following fix, or wait for the next Windows NT service pack.

This hotfix has been posted to the following Internet location:

ftp://ftp.microsoft.com/bussys/winnt/winnt-public/fixes/usa/NT40/hotfixes-postSP2/dns-fix

MORE INFORMATION

For additional information, please see the following article in the Microsoft Knowledge Base:

Article-ID: Q169461
TITLE: Access Violation in DNS.EXE Caused by Malicious Telnet Attack

STATUS

Microsoft has confirmed this to be a problem in Windows NT version 4.0. This problem was corrected in the latest Microsoft Windows NT 4.0 U.S. Service Pack. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K

Additional query words: dns prodnt telnet denial of service

Keywords : kbbug4.00 nttcp kbfix4.00.sp3 NTSrv
Version : WinNT:4.0
Platform : winnt
Issue type :