Microsoft Security Bulletin MS99-024
Patch Available for "Unprotected IOCTLs" Vulnerability
Patch Availability Information Updated: March 10, 2003
Originally Posted: July 06, 1999
Microsoft has released a patch that eliminates a vulnerability that could allow denial of service attacks against a Microsoft® Windows NT® workstation, server or terminal server. An unprivileged program can disable the local mouse or keyboard on a server or workstation, and disable the console mouse or keyboard on a terminal server.
Frequently asked questions regarding this vulnerability can be found at http://www.microsoft.com/technet/security/bulletin/fq99-024.mspx
The IOCTLs that are used to obtain services from the keyboard and mouse drivers in Windows NT do not require that the calling program have administrative privileges. A user-level program could use legitimate calls to disable the mouse and keyboard, after which the machine would need to be rebooted to restore normal service. On a terminal server, such a program could disable the keyboard and mouse on the console.
Affected Software Versions
- Microsoft Windows NT Workstation 4.0
- Microsoft Windows NT Server 4.0
- Microsoft Windows NT Server 4.0, Enterprise Edition
- Microsoft Windows NT Server 4.0, Terminal Server Edition
Vulnerability Identifier: CVE-1999-0728
- Windows NT Server and Workstation 4.0: http://www.microsoft.com/technet/security/patchavailability.mspx
- Windows NT Server 4.0, Terminal Server Edition: http://www.microsoft.com/technet/security/patchavailability.mspx
Please see the following references for more information related to this issue.
- Microsoft Security Bulletin MS99-024: Frequently Asked Questions, http://www.microsoft.com/technet/security/bulletin/fq99-024.mspx.
- Microsoft Knowledge Base (KB) article 236359, Denial of Service Attack Using Unprotected IOCTL Function Call, http://support.microsoft.com/default.aspx?scid=kb;en-us;236359&sd=tech
(Note It may take 24 hours from the original posting of this bulletin for the KB article to be visible; however, a copy will be immediately available in the patch folder.)
- 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/contactussupport/?ws=support.
Microsoft acknowledges Mark Russinovich of Systems Internals for discovering this vulnerability and reporting it to us.
- July 06, 1999: Bulletin Created.
- V2.0 (March 10, 2003): Introduced versioning and updated patch availability information
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