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Microsoft Security Program: Microsoft Security Bulletin (MS99-033)

Patch Available for "Malformed Telnet Argument" Vulnerability

Originally Posted: September 09, 1999

Summary

Microsoft has released a patch that eliminates a vulnerability in the Telnet client that ships as part of Microsoft® Windows® 95 and 98. The vulnerability could allow arbitrary code to be executed on the user's computer.

Frequently asked questions regarding this vulnerability can be found at http://www.microsoft.com/technet/security/bulletin/fq99-033.mspx

Issue

The Telnet client that ships as part of Windows 95 and 98 has an unchecked buffer. A specially-malformed argument could be passed to the client via a web page in order to cause arbitrary code to execute on the computer via a classic buffer overrun technique.

Affected Software Versions

•	Microsoft Windows 95
•	Microsoft Windows 98
•	Microsoft Windows 98 Second Edition

Vulnerability Identifier: CVE-1999-0749

Patch Availability

•

Microsoft Windows 95

http://www.microsoft.com/windows95/downloads/contents/WUCritical/Telnet/Default.asp

•

Microsoft Windows 98 and Windows 98 Second Edition

http://www.microsoft.com/windows98/downloads/contents/WUCritical/Telnet/Default.asp

Note This patch also is available via WindowsUpdate.

More Information

Please see the following references for more information related to this issue.

•	Microsoft Security Bulletin MS99-033: Frequently Asked Questions, http://www.microsoft.com/technet/security/bulletin/fq99-033.mspx.
•	Microsoft Security web site, http://www.microsoft.com/technet/security/default.mspx

Obtaining Support on this Issue

This is a fully supported patch. Information on contacting Microsoft Technical Support is available at http://support.microsoft.com/support/contact/default.asp.

Acknowledgments

Microsoft acknowledges Jeremy Kothe for bringing this issue to our attention.

Revisions

•	September 09, 1999: Bulletin Created.

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