Published:
23 November 2000
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-----BEGIN PGP SIGNED MESSAGE----- =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2000.370 -- Microsoft Security Bulletin (MS00-090) Patch Available for ".ASX Buffer Overrun" and ".WMS Script Execution" 24 November 2000 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: Windows Media Player 6.4 and 7 Vendor: Microsoft Impact: Execute Arbitrary Code/Commands Access Required: Remote - --------------------------BEGIN INCLUDED TEXT-------------------- - -----BEGIN PGP SIGNED MESSAGE----- Microsoft Security Bulletin (MS00-090) - - -------------------------------------- Patch Available for ".ASX Buffer Overrun" and ".WMS Script Execution" Vulnerabilities Originally posted: November 22, 2000 Summary ======= Microsoft has released a patch that eliminates two security vulnerabilities in Microsoft(r) Windows Media(tm) Player. These vulnerabilities could potentially enable a malicious user to cause a program of his choice to run on another user's computer. Frequently asked questions regarding this vulnerability and the patch can be found at http://www.microsoft.com/technet/security/bulletin/fq00-090.asp Issue ===== The two vulnerabilities discussed below are unrelated to each other except by the fact that they both affect Windows Media Player. We packaged them in a single patch to make it more convenient for customers to apply. The vulnerabilities are: - The ".ASX Buffer Overrun" vulnerability. Windows Media Player supports the use of Active Stream Redirector (.ASX) files to enable users to play streaming media that resides on intranet or Internet sites. However, the code that parses .ASX files has an unchecked buffer, and this could potentially enable a malicious user to run code of his choice on the machine of another user. The malicious user could either send an affected file to another user and entice her to run or preview it, or he could host such a file on a web site and cause it to launch automatically whenever a user visited the site. The code could take any action on the machine that the legitimate user herself could take. - The ".WMS Script Execution" vulnerability. Windows Media Player 7 introduced a feature called "skins", that allows customization of the look and feel of Windows Media Player. However, a custom skin (.WMS) file could potentially include script, which would execute if Windows Media Player was run and that skin was selected. A malicious user could either send a customized skin containing script to another user and try to entice her into using it, or he could host such a file on a web site and cause it to launch automatically whenever a user visited the site. Because the code would reside on the user's local machine, it would be able to execute ActiveX controls, including ones not marked "safe for scripting". This would enable the code to take any action that can be accomplished via an ActiveX control. Affected Software Versions ========================== - Microsoft Windows Media Player 6.4 - Microsoft Windows Media Player 7 Note: The ".ASX Buffer Overrun" affects Windows Media Player versions 6.4 and 7. The ".WMS Script Execution" affects only Windows Media Player version 7. The patch installs the correct fix(es) for the particular version of Windows Media Player in use. Patch Availability ================== - Windows Media Player 6.4: http://www.microsoft.com/Downloads/Release.asp?ReleaseID=26069 - Windows Media Player 7: http://www.microsoft.com/Downloads/Release.asp?ReleaseID=26067 Note: The fix for this issue also will be available as part of the next periodic update, scheduled for December 2000. Note: Additional security patches are available at the Microsoft Download Center More Information ================ Please see the following references for more information related to this issue. - Frequently Asked Questions: Microsoft Security Bulletin MS00-090, http://www.microsoft.com/technet/security/bulletin/fq00-090.asp - Microsoft Knowledge Base article Q280419 discusses this issue and will be available soon. - Microsoft TechNet Security web site, http://www.microsoft.com/technet/security/default.asp Obtaining Support on this Issue =============================== This is a fully supported patch. Information on contacting Microsoft Product Support Services is available at http://support.microsoft.com/support/contact/default.asp. Acknowledgments =============== Microsoft thanks the following people: - AtStake (http://www.atstake.com) for reporting the ".ASX Buffer Overrun" issue to us and working with us to protect customers. - GFI (http://gfi.com) for reporting the ".WMS Script Execution" vulnerability to us and working with us to protect customers. Revisions ========= - November 22, 2000: Bulletin Created. - - ------------------------------------------------------- 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. - -----BEGIN PGP SIGNATURE----- Version: PGP Personal Privacy 6.5.3 iQEVAwUBOh00G40ZSRQxA/UrAQG1dwgAgALyGDXfypSlyjatp3OaHcdvxjw9emhF DVLjPYtVfpfQFq0eIHMTETBnBUTnKNnt13oWFS9boq5w3kyY30NmkmLALntaV5RA LUAiuhe41sTO5Ns3+6iqQiTKGTrK9/3vXurb157s8eujo0snIwLsnS2DOC5tORQv uyfvzeT6tKk9O/z6lqFH7BHxgNm0iqGgr02dPloU21KFAhjJK6zAsoMuuSSiJmL6 7I12/6snq2XjfhpgqA1grSfNSDUrvVHnmcfYtLZxyOKHN1TT+MSKyZfZOLh6CQOC 39BaqOfd/zssiXtqSiXXEVkH3UJmXXGaIz4JNeqig6qR3aQ8XGRHPw== =KLx9 - -----END PGP SIGNATURE----- - --------------------------END INCLUDED TEXT-------------------- This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. 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Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for emergencies. -----BEGIN PGP SIGNATURE----- Version: 2.6.3i Charset: noconv Comment: ftp://ftp.auscert.org.au/pub/auscert/AUSCERT_PGP.key iQCVAwUBOlSNWyh9+71yA2DNAQGT8AP+Mdg7AdCxe3R9thwMP/vyAyRprH2SU83L V5b3TPDovEQps1+NN6gipSFa+Lf7vbip66Fkvk9RhN5VK3oCa363nVS5L02k1FPo ZXgKFpJ0G3CNm8SscgCUIodPdMHlGvCvPvzT29d/gKpkMn8p+Zfu3B27hROY3WWQ o2mRGX7j1rw= =rBaU -----END PGP SIGNATURE-----