DOCUMENT:Q283001 08-MAY-2002 [winnt] TITLE :MS01-009: Patch Available for Malformed PPTP Packet Stream Vulne PRODUCT :Microsoft Windows NT PROD/VER::4.0,4.0 SP1,4.0 SP2,4.0 SP3,4.0 SP4,4.0 SP5,4.0 SP6,4.0 SP6a OPER/SYS: KEYWORDS:kbenv kbpatch kbSecurity kbWinNT400PreSP7Fix kbgraphxlinkcritical KbSECVulnerability Kb ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server versions 4.0, 4.0 SP1, 4.0 SP2, 4.0 SP3, 4.0 SP4, 4.0 SP5, 4.0 SP6a - Microsoft Windows NT Server, Enterprise Edition versions 4.0, 4.0 SP4, 4.0 SP5, 4.0 SP6a - Microsoft Windows NT Server versions 4.0, 4.0 SP4, 4.0 SP5, 4.0 SP6, Terminal Server Edition ------------------------------------------------------------------------------- SYMPTOMS ======== Microsoft has released a patch that eliminates a security vulnerability that affects Windows NT 4.0-based servers that provide secure remote sessions. The vulnerability may allow a malicious user to prevent an affected computer from providing service. The Point-to-Point Tunneling Protocol (PPTP) service has a security vulnerability in the code that handles a certain type of data packet, which results in a leak of kernel memory. If a sufficient number of packets that contain a specific malformation are received by an affected server, kernel memory eventually becomes exhausted. This can cause the server to stop responding (hang). When the computer hangs, you must reboot the computer. Note that any PPTP sessions that are running are lost when you reboot the computer. The malicious user does not need to establish a valid PPTP session to exploit the vulnerability. The vulnerability does not threaten the security of the data in PPTP sessions in any way; it is strictly a denial-of-service vulnerability. Computers that are running the PPTP service are the only computers that are affected by this vulnerability (the service does not run by default). Windows 2000-based computers, including Windows 2000-based computers that are running PPTP, are not affected by this vulnerability. RESOLUTION ========== Windows NT 4.0 -------------- To resolve this problem, obtain the individual package referenced below or obtain the Windows NT 4.0 Security Rollup Package. For additional information on the SRP, click the article number below to view the article in the Microsoft Knowledge Base: Q299444 Post-Windows NT 4.0 Service Pack 6a Security Rollup Package (SRP) The following files are available for download from the Microsoft Download Center: US English: DownloadDownload Q283001i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=27836) German: DownloadDownload Deuq283001i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=27844) For additional information about how to download Microsoft Support files, click the article number below to view the article in the Microsoft Knowledge Base: Q119591 How to Obtain Microsoft Support Files from Online Services Microsoft used the most current virus detection software available on the date of posting to scan this file for viruses. After it is posted, the file is housed on secure servers that prevent any unauthorized changes to the file. The English-language version of this fix should have the following file attributes or later: Date Time Version Size File name Platform ----------------------------------------------------------------- 12/07/2000 11:48p 4.0.1381.7086 41,008 Raspptpe.sys Intel 12/07/2000 11:46p 4.0.1381.7086 76,592 Raspptpe.sys Alpha NOTE: Due to file dependencies, this hotfix requires Microsoft Windows NT 4.0 Service Pack 6a (SP6a). Windows NT Server 4.0, Terminal Server Edition ---------------------------------------------- To resolve this problem, either obtain the hotfix referenced in this section or the Windows NT Server 4.0, Terminal Server Edition, Security Rollup Package (SRP). For additional information about the SRP, click the article number below to view the article in the Microsoft Knowledge Base: Q317636 Windows NT Server 4.0, Terminal Server Edition, Security Rollup Package A supported fix is now available from Microsoft, but it is only intended to correct the problem described in this article and should be applied only to systems that are determined to be at risk of attack. Please evaluate your computer's physical accessibility, network and Internet connectivity, and other factors to determine the degree of risk to your computer. Please see the associated Microsoft Security Bulletin (http://www.microsoft.com/technet/security/bulletin/ms01-009.asp) to help make this determination. This fix may receive additional testing at a later time, to further ensure product quality. If your computer is sufficiently at risk, Microsoft recommends that you apply this fix now. To resolve this problem immediately, download the fix as instructed below or contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web: http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS NOTE: In special cases, charges that are normally incurred for support calls may be canceled, if a Microsoft Support Professional determines that a specific update will resolve your problem. Normal support costs will apply to additional support questions and issues that do not qualify for the specific update in question. The English-language version of this fix should have the following file attributes or later: Date Time Version Size File name Platform ----------------------------------------------------------------- 12/07/2000 11:48p 4.0.1381.7086 41,008 Raspptpe.sys Intel 12/07/2000 11:46p 4.0.1381.7086 76,592 Raspptpe.sys Alpha NOTE: Due to file dependencies, this hotfix requires Microsoft Windows NT Server 4.0, Terminal Server Edition Service Pack 6 (SP6). STATUS ====== Windows NT 4.0 -------------- Microsoft has confirmed that this problem could result in some degree of security vulnerability in Windows NT 4.0. Windows NT Server 4.0, Terminal Services Edition ------------------------------------------------ Microsoft has confirmed that this problem could result in some degree of security vulnerability in Windows NT Server 4.0, Terminal Server Edition. MORE INFORMATION ================ For more information about this vulnerability, view the following Microsoft Web site: http://www.microsoft.com/technet/security/bulletin/ms01-009.asp Additional query words: security_patch kbtse srp ====================================================================== Keywords : kbenv kbpatch kbSecurity kbWinNT400PreSP7Fix kbgraphxlinkcritical KbSECVulnerability KbSECBulletin Technology : kbWinNTsearch kbWinNT400search kbWinNTSsearch kbWinNTSEntSearch kbWinNTSEnt400sp5 kbWinNTSEnt400sp4 kbWinNTSEnt400 kbWinNTS400sp6 kbWinNTS400sp5 kbWinNTS400sp4 kbWinNTS400sp3 kbWinNTS400sp2 kbWinNTS400sp1 kbWinNTS400search kbWinNTS400 kbNTTermServ400 kbNTTermServ400sp4 kbNTTermServ400sp5 kbNTTermServ400sp6 kbNTTermServSearch kbWinNTSEnt400SP6a Version : :4.0,4.0 SP1,4.0 SP2,4.0 SP3,4.0 SP4,4.0 SP5,4.0 SP6,4.0 SP6a Hardware : ALPHA x86 Issue type : kbbug Solution Type : kbfix ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2002.