XADM: TNS Resolution Causes Buffer Overflow (157691)



The information in this article applies to:

  • Microsoft Exchange Server 4.0

This article was previously published under Q157691

SYMPTOMS

Federal sites needing to use Tactical Name Service (TNS) instead of Domain Name Service (DNS), will encounter the following issue. When Microsoft Exchange looks to connect to another SMTP server, it queries the TNS for an MX Record (SMTP address). If the address is present, everything works fine. If the address is not present, the TNS server sends its own IP address. If the Server hardware is an old UNIX computer, with a total input buffer of 200k, the Microsoft Exchange mail headers will cause a buffer overflow.

MORE INFORMATION

Basic TNS information:
  1. It is run on a special version of UNIX that the U.S. ARMY developed.

    It includes only 1 zone.

    It only listens on one IP address.

    It dynamically registers hosts.

    It does not support MX priority/preference values.

    It does not support SOA records.
  2. It includes only 1 zone.

    It only listens on one IP address.

    It dynamically registers hosts.

    It does not support MX priority/preference values.

    It does not support SOA records.
  3. It only listens on one IP address.

    It dynamically registers hosts.

    It does not support MX priority/preference values.

    It does not support SOA records.
  4. It dynamically registers hosts.

    It does not support MX priority/preference values.

    It does not support SOA records.
  5. It does not support MX priority/preference values.

    It does not support SOA records.
  6. It does not support SOA records.

STATUS

Microsoft has confirmed this to be a problem in Microsoft Exchange Server version 4.0. This problem was corrected in the latest Microsoft Exchange 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


Modification Type:MinorLast Reviewed:4/28/2005
Keywords:kbusage KB157691