Date: Wed, 21 Apr 1999 18:13:39 -0700 From: aleph1@UNDERGROUND.ORG To: BUGTRAQ@netspace.org Subject: Microsoft Security Bulletin (MS99-011) The following is a Security Bulletin from the Microsoft Product Security Notification Service. Please do not reply to this message, as it was sent from an unattended mailbox. ******************************** Microsoft Security Bulletin (MS99-011) -------------------------------------- Patch Available for "DHTML Edit" Vulnerability Originally Posted: April 21, 1999 Summary ======= Microsoft has released a patch that eliminates a vulnerability in an ActiveX control that is distributed in Internet Explorer 5 and downloadable for Internet Explorer 4.0. The vulnerability could allow a malicious web site operator to read information that a user had loaded into the control, and it also could allow files with known names to be copied from the user's local hard drive. A fully supported patch is available to eliminate this vulnerability and Microsoft recommends that affected customers download and install it, if appropriate. Issue ===== The DHTML Edit control is an ActiveX control that is distributed with Internet Explorer 5 and can be downloaded for use in Internet Explorer 4.0. The control enables users to edit HTML text and see a faithful rendition of how the text would look in the browser. There are two versions of the control: a more powerful version that cannot be invoked by a web site because it includes file access and other features, and a "safe for scripting" version that has restricted functionality and is intended for use by web sites. The root cause of the vulnerability lies in the fact that a web site that hosts the "safe for scripting" version of the control is able to upload any data entered into the control. A malicious web site operator could trick a user into entering sensitive data into a DHTML Edit control hosted on a web page from the operator's site, and then upload the data. In addition, if the malicious web site operator knows the name of a file on the user's local drive, it is possible for the operator to programmatically load the file into the control and then upload it. The patch works by allowing a web site to load data from the control only if it is in the site's domain. While there are no reports of customers being adversely affected by this vulnerability, Microsoft is proactively releasing this patch to allow customers to take appropriate action to protect themselves against it. Affected Software Versions ========================== - Microsoft Internet Explorer 5 on Windows 95, Windows 98, and Windows NT 4.0. Internet Explorer 5 on other platforms is not affected. - Microsoft Internet Explorer 4.0 on Windows 95, Windows 98 and the x86 version of Windows NT 4.0. Internet Explorer 4.0 on other platforms, including the Alpha version of Windows NT 4.0, is not affected. Note: The DHTML Edit control is included by default in Internet Explorer 5. It is not included by default in Internet Explorer 4.0, but can be downloaded and installed. Internet Explorer 4.0 customers who are unsure whether they have installed the control should see What Customers Should Do. What Microsoft is Doing ======================= Microsoft has released patches that fix the problem identified. The patches are available for download from the sites listed below in What Customers Should Do. Microsoft also has sent this security bulletin to customers subscribing to the Microsoft Product Security Notification Service. See http://www.microsoft.com/security/services/bulletin.asp for more information about this free customer service. Microsoft has published the following Knowledge Base (KB) article on this issue: - Microsoft Knowledge Base (KB) article Q226326, Update Available for 'DHTML Edit' Security Issue, http://support.microsoft.com/support/kb/articles/q226/3/26.asp. (Note: It might take 24 hours from the original posting of this bulletin for the KB article to be visible in the Web-based Knowledge Base.) What Customers Should Do ======================== Microsoft highly recommends that customers determine whether they are potentially affected by the vulnerability: - All copies of Internet Explorer 5 contain the DHTML Edit control, so all Internet Explorer 5 customers are potentially affected by the vulnerability. - The only Internet Explorer 4.0 users who are potentially affected by the vulnerability are those who have downloaded and installed the DHTML Edit control. If this has been done, the file dhtmled.ocx will be present on the hard drive. By default, this file will be stored in the folder C:\Program Files\Common Files\Microsoft Shared\Triedit\. Customers who are potentially affected by the vulnerability should evaluate the degree of risk that this vulnerability poses to their systems and determine whether to download and install the patch. The patch can be found at http://www.microsoft.com/windows/ie/security/dhtml_edit.asp. More Information ================ Please see the following references for more information related to this issue. - Microsoft Security Bulletin MS99-011, Patch Available for DHTML Edit Vulnerability. (The Web-posted version of this bulletin), http://www.microsoft.com/security/bulletins/ms99-011.asp. - Microsoft Knowledge Base (KB) article Q226326, Update Available for 'DHTML Edit' Security Issue, http://support.microsoft.com/support/kb/articles/q226/3/26.asp. (Note: It might take 24 hours from the original posting of this bulletin for the KB article to be visible in the Web-based Knowledge Base.) Obtaining Support on this Issue =============================== If you require technical assistance with this issue, please contact Microsoft Technical Support. For information on contacting Microsoft Technical Support, please see http://support.microsoft.com/support/contact/default.asp. Acknowledgments =============== Microsoft acknowledges Juan Carlos Cuartango of Spain for discovering this vulnerability and reporting it to us. Revisions ========= - April 21, 1999: Bulletin Created. For additional security-related information about Microsoft products, please visit http://www.microsoft.com/security -------------------------------------------------------------------- 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. (c) 1999 Microsoft Corporation. All rights reserved. ******************************************************************* You have received this e-mail bulletin as a result of your registration to the Microsoft Product Security Notification Service. You may unsubscribe from this e-mail notification service at any time by sending an e-mail to MICROSOFT_SECURITY-SIGNOFF-REQUEST@ANNOUNCE.MICROSOFT.COM The subject line and message body are not used in processing the request, and can be anything you like. For more information on the Microsoft Security Notification Service please visit http://www.microsoft.com/security/bulletin.htm. For security-related information about Microsoft products, please visit the Microsoft Security Advisor web site at http://www.microsoft.com/security. --------------------------------------------------------------------------------- Date: Wed, 21 Apr 1999 18:14:00 -0700 From: aleph1@UNDERGROUND.ORG To: BUGTRAQ@netspace.org Subject: Microsoft Security Bulletin (MS99-012) The following is a Security Bulletin from the Microsoft Product Security Notification Service. Please do not reply to this message, as it was sent from an unattended mailbox. ******************************** Microsoft Security Bulletin (MS99-012) -------------------------------------- MSHTML Update Available for Internet Explorer Originally Posted: April 21, 1999 Summary ======= Microsoft has released an updated version of a component of Internet Explorer 4.0 and 5. The updated version eliminates three security vulnerabilities described below. It is fully supported and Microsoft recommends that affected customers download and install it, if appropriate. Issue ===== MSHTML.DLL is the parsing engine for HTML in Internet Explorer. The vulnerabilities that are eliminated by the update are not related to each other except for the fact that all reside within the parsing engine. - The first vulnerability is a privacy issue involving the processing of the "IMG SRC" tag in HTML files. This tag identifies and loads image sources - image files that are to be displayed as part of a web page. The vulnerability results because the tag can be used to point to files of any type, rather than only image files, after which point the document object model methods can be used to determine information about them. A malicious web site operator could use this vulnerability to determine the size and other information about files on the computer of a visiting user. It would not allow files to be read or changed, and the malicious web site operator would need to know the name of each file. - The second vulnerability is a new variant of a previously-identified cross-frame security vulnerability. A particular malformed URL could be used to execute scripts in the security context of a different domain. This could allow a malicious web site operator to execute a script on the web site, and gain privileges on visiting users' machines that are normally granted only to their trusted sites. - The third vulnerability affects only Internet Explorer 5.0, and is a new variant of a previously-identified untrusted scripted paste vulnerability. The vulnerability would allow a malicious web site operator to create a particular type of web page control and paste into it the contents of a visiting user's clipboard. While there are no reports of customers being adversely affected by any of these vulnerabilities, Microsoft is proactively releasing an updated version of MSHTML.DLL to allow customers to take appropriate action to protect themselves against it. Affected Software Versions ========================== - Internet Explorer 4.0 and 5 on Windows 95, Windows 98 and Windows NT 4.0. What Microsoft is Doing ======================= Microsoft has released patches that fix the problem identified. The patches are available for download from the sites listed below in What Customers Should Do. Microsoft also has sent this security bulletin to customers subscribing to the Microsoft Product Security Notification Service. See http://www.microsoft.com/security/services/bulletin.asp for more information about this free customer service. Microsoft has published the following Knowledge Base (KB) article on this issue: - Microsoft Knowledge Base (KB) article Q226326, Update Available for MSHTML Security Issues in Internet Explorer, http://support.microsoft.com/support/kb/articles/q226/3/26.asp. (Note: It might take 24 hours from the original posting of this bulletin for the KB article to be visible in the Web-based Knowledge Base.) What Customers Should Do ======================== Microsoft highly recommends that customers evaluate the degree of risk that this vulnerability poses to their systems and determine whether to download and install the patch. The patch can be found at http://www.microsoft.com/windows/ie/security/mshtml.asp. More Information ================ Please see the following references for more information related to this issue. - Microsoft Security Bulletin MS99-012, MSHTML Update Available for Internet Explorer (The Web-posted version of this bulletin), http://www.microsoft.com/security/bulletins/ms99-012.asp. - Microsoft Knowledge Base (KB) article Q226326, Update Available for MSHTML Security Issues in Internet Explorer, http://support.microsoft.com/support/kb/articles/q226/3/26.asp. - Microsoft Security Bulletin MS98-013, Fix available for Internet Explorer Cross Frame Navigate Vulnerability, http://www.microsoft.com/security/bulletins/ms98-013.asp - Microsoft Security Bulletin MS98-015, Update available for "Untrusted Scripted Paste" Issue in Microsoft Internet Explorer 4.01, http://www.microsoft.com/security/bulletins/ms98-015.asp Obtaining Support on this Issue =============================== If you require technical assistance with this issue, please contact Microsoft Technical Support. For information on contacting Microsoft Technical Support, please see http://support.microsoft.com/support/contact/default.asp. Acknowledgments =============== Microsoft acknowledges Richard M. Smith, President, Phar Lap Software, Inc., for discovering the IMG SRC vulnerability, and Georgi Guninski from TechnoLogica Ltd., Bulgaria, for discovering the cross-frame and untrusted scripted paste vulnerabilities. Revisions ========= - April 21, 1999: Bulletin Created. For additional security-related information about Microsoft products, please visit http://www.microsoft.com/security ---------------------------------------------------------------------- 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. (c) 1999 Microsoft Corporation. All rights reserved. ******************************************************************* You have received this e-mail bulletin as a result of your registration to the Microsoft Product Security Notification Service. You may unsubscribe from this e-mail notification service at any time by sending an e-mail to MICROSOFT_SECURITY-SIGNOFF-REQUEST@ANNOUNCE.MICROSOFT.COM The subject line and message body are not used in processing the request, and can be anything you like. For more information on the Microsoft Security Notification Service please visit http://www.microsoft.com/security/bulletin.htm. For security-related information about Microsoft products, please visit the Microsoft Security Advisor web site at http://www.microsoft.com/security. --------------------------------------------------------------------------------- Date: Thu, 22 Apr 1999 03:28:52 -0400 From: Russ To: NTBUGTRAQ@LISTSERV.NTBUGTRAQ.COM Subject: Alert: Microsoft Security Bulletin (MS99-012) - MSHTML.dll Note: URLs may be line wrapped Microsoft have released a Security Bulletin; http://www.microsoft.com/security/bulletins/ms99-012.asp which covers 3 issues with the MSHTML.dll component of IE 4.0 and IE 5.0 (MSHTML is responsible for parsing URLs). The first issue was discovered by Richard Smith of Pharlap (and not reported to NTBugtraq) and has to do with IMG SRC tags (which allowed them to load local files). The other 2 issues were discovered by Georgi Guninski and reported in NTBugtraq messages; Trust Zone vulnerability: http://ntbugtraq.ntadvice.com/default.asp?pid=36&sid=1&A2=ind9903&L=ntbu gtraq&F=P&S=&P=16238 Cross-frame vulnerability: http://ntbugtraq.ntadvice.com/default.asp?pid=36&sid=1&A2=ind9904&L=ntbu gtraq&F=P&S=&P=1516 on March 30th and April 9th respectively. It should be noted that installation of the replacement MSHTML.dll requires a reboot! The fix location is; http://www.microsoft.com/windows/ie/security/mshtml.asp execution of Georgi's demonstration pages (after rebooting!); Trust Zone vulnerability: http://www.nat.bg/~joro/scrspoof.html Cross-frame vulnerability: http://www.nat.bg/~joro/fr.html shows nothing unexpected. While the Bulletin states that the same MS Knowledgebase article, Q226326, applies to both MS99-011 and MS99-012, it was *not* available at the time of this writing (meaning it was there 10 minutes ago, but its not there now??). See; http://support.microsoft.com/support/kb/articles/q226/3/26.asp I just take this opportunity to say that I think Microsoft needs to make everyone aware of any installation process that requires a reboot to complete. There is no mention anywhere that fixing a browser component would require a system reboot, and while I can understand why its needed (having experience and all), no doubt lots of folks wouldn't expect it to be a requirement (although lots of folks likely believe that everything you do to an NT box requires a reboot!). The DHMTL fix doesn't require a reboot, but the MSHTML fix does. Given that both download pages recommend that you "Open" or "Run" the download, causing it to execute, one could easily find oneself in the position of being prompted for a reboot when you didn't expect one. Even the "detailed instructions" don't acknowledge that a reboot is required. A simple large, bold, message at the top of any download page indicating what will be expected if the download is "Open" or "Run" might at least acknowledge that too many reboots are expected by Microsoft. Cheers, Russ - NTBugtraq moderator --------------------------------------------------------------------------------- Date: Thu, 22 Apr 1999 15:39:14 -0700 From: Aleph One To: NTBUGTRAQ@LISTSERV.NTBUGTRAQ.COM Subject: Re: Alert: Microsoft Security Bulletin (MS99-012) - MSHTML.dll On Thu, Apr 22, 1999 at 03:28:52AM -0400, Russ wrote: > > Cross-frame vulnerability: > http://www.nat.bg/~joro/fr.html I believe that is incorrect. That is an example of the other file stealing vulnerability in the DHTML Edit component. Yes, there where two of them in the same component. The cross-frame vulnerability test are: http://www.nat.bg/~joro/scrspoof.htmlasd http://www.nat.bg/~joro/scriptlet.html http://www.nat.bg/~joro/scrauto.html -- Aleph One / aleph1@underground.org http://underground.org/ KeyID 1024/948FD6B5 Fingerprint EE C9 E8 AA CB AF 09 61 8C 39 EA 47 A8 6A B8 01