CERT^® Incident Note IN-99-08

Attacks against IIS web servers involving MDAC

We have received reports of IIS web servers compromised via a vulnerability in MS Data Access Components (MDAC). This vulnerability has been widely discussed as early as April 22, 1998. Here are some pointers to information about this vulnerability:

http://support.microsoft.com/support/kb/articles/q184/3/75.asp

http://www.microsoft.com/security/bulletins/ms98-004.asp

http://www.microsoft.com/security/bulletins/ms99-025.asp

In incidents reported to us so far, attacks can be identified by looking through the IIS log files for POST access to the file "/msadc/msadcs.dll". For example:

1999-10-24 20:38:12  - WWW  POST /msadc/msadcs.dll 200 1409 664 782 ACTIVEDATA - -

If you use Microsoft Remote Data Services (RDS) these POST operations may be legitimate.

We encourage all sites using IIS to carefully follow the steps listed in Microsoft Advisory MS99-025, referenced above, to secure or disable RDS.

CERT/CC Contact Information

Email: cert@cert.org
Phone: +1 412-268-7090 (24-hour hotline)
Fax: +1 412-268-6989
Postal address:

CERT Coordination Center
Software Engineering Institute
Carnegie Mellon University
Pittsburgh PA 15213-3890
U.S.A.

CERT/CC personnel answer the hotline 08:00-17:00 EST(GMT-5) / EDT(GMT-4) Monday through Friday; they are on call for emergencies during other hours, on U.S. holidays, and on weekends.

Using encryption

We strongly urge you to encrypt sensitive information sent by email. Our public PGP key is available from

http://www.cert.org/CERT_PGP.key

If you prefer to use DES, please call the CERT hotline for more information.

Getting security information

CERT publications and other security information are available from our web site

http://www.cert.org/

* "CERT" and "CERT Coordination Center" are registered in the U.S. Patent and Trademark Office.

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