Stop 0A in Tcpip.sys When Receiving Out Of Band (OOB) Data

A Stop 0x0000000A occurs in Tcpip.sys when receiving Out of Band (OOB) data.

A sender specifies "Out of Band" data by setting the URGENT bit flag in the TCP header. The receiver uses the URGENT POINTER to determine where in the segment the urgent data ends. Windows NT bugchecks when the URGENT POINTER points to the end of the frame and no normal data follows. Windows NT expects normal data to follow.

Microsoft has updated Tcpip.sys to correct the problem. Instructions for installing it are available from Microsoft support channels, or directly from the Internet locations below.

NOTE: This hotfix was originally posted on May 12, 1997. A subsequent fix was completed on January 9, 1998, to address another nearly identical attack and this hotfix has replaced the original one. The original hotfix is included in Windows NT 4.0 Service Pack 3. The most recent hotfix is not; however, it is available from the following Internet locations:

Windows NT 4.0 SP2

NOTE: Service pack 2 must be applied to Windows NT 4.0 prior to applying this fix.

This hotfix has been posted to the following Internet location:

Windows NT 4.0 SP3

NOTE: Service pack 3 must be applied to Windows NT 4.0 prior to applying this fix.

Oob-fix and Icmp-fix have been superseded by Teardrop2-fix. For your convenience, the English version of this post-SP3 hotfix has been posted to the following Internet location. However, Microsoft recommends that you install Windows NT 4.0 Service Pack 4 to correct this problem.

This fix should have the following time stamp:



For your convenience, the English version of this post-SP3 hotfix has been posted to the following Internet location. However, Microsoft recommends that you install Windows NT 4.0 Service Pack 4 to correct this problem.


WARNING: If you install the original (archived) version of this hotfix AFTER you apply the later version, your system may become unusable. Microsoft does not recommend you install the original hotfix after applying the later version.

To resolve this problem, obtain the latest service pack for Windows NT 4.0 or Windows NT Server 4.0, Terminal Server Edition. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

Windows NT 3.51

NOTE: Service pack 5 must be applied to Windows NT 3.51 prior to applying this fix.

This hotfix has been posted to the following Internet location:

This fix should have the following time stamp:

Windows NT 4.0

Microsoft has confirmed this problem could result in some degree of security vulnerability in Windows NT version 4.0. This problem was first corrected in Windows NT 4.0 Service Pack 4.0 and Windows NT Server 4.0, Terminal Server Edition Service Pack 4.

Windows NT 3.51

Microsoft has confirmed this problem could result in some degree of security vulnerability in Windows NT version 3.51. A fully supported fix is now available, but it has not been fully regression tested and should only be applied to systems determined to be at risk of attack. Please evaluate your system's physical accessibility, network and Internet connectivity, and other factors to determine the degree of risk to your system. If your system is sufficiently at risk, Microsoft recommends you apply this fix. Otherwise, wait for the next Windows NT service pack, which will contain this fix. Please contact Microsoft Technical Support for more information.