From 0_29385_AE7F5476-145E-455E-9095-807DF5278AEC_US@Newsletters.Microsoft.com Thu Apr 18 13:07:40 2002 From: Microsoft <0_29385_AE7F5476-145E-455E-9095-807DF5278AEC_US@Newsletters.Microsoft.com> To: bugtraq@securityfocus.com Date: Wed, 17 Apr 2002 06:06:26 -0700 Reply-To: 3_29385_AE7F5476-145E-455E-9095-807DF5278AEC_US@Newsletters.Microsoft.com Subject: Microsoft Security Bulletin MS02-019: Unchecked Buffer in Internet Explorer and Office for Mac Can Cause Code to Execute (Q321309) [The following text is in the "iso-8859-1" character set] [Your display is set for the "US-ASCII" character set] [Some characters may be displayed incorrectly] -----BEGIN PGP SIGNED MESSAGE----- - ---------------------------------------------------------------------- Title: Unchecked Buffer in Internet Explorer and Office for Mac Can Cause Code to Execute (Q321309) Date: 16 April 2002 Software: Microsoft Internet Explorer 5.1 for Macintosh, Microsoft Outlook Express 5.0 for Macintosh, Microsoft Office v. X, for Macintosh, Microsoft Office 2001 for Macintosh, Microsoft PowerPoint 98 for Macintosh Impact: Run Code of Attacker's Choice Max Risk: Critical Bulletin: MS02-019 Microsoft encourages customers to review the Security Bulletin at: http://www.microsoft.com/technet/security/bulletin/MS02-019.asp. - - - ---------------------------------------------------------------------- Issue: ====== This is a cumulative patch that, when applied, eliminates all previously released security vulnerabilities affecting IE 5.1 for Macintosh, and Office v. X for Macintosh. In addition, it eliminates two newly discovered vulnerabilities. - The first is a buffer overrun vulnerability associated with the handling of a particular HTML element. Because of support for HTML in Office applications, this flaw affects both IE and Office for Macintosh. A security vulnerability results because an attacker can levy a buffer overrun attack against IE that attempts to exploit this flaw. A successful attack would have the result of causing the program to fail, or to cause code of the attacker's choice to run as if it were the user. - The second is a vulnerability that can allow local AppleScripts to be invoked by a web page. This vulnerability can allow locally stored AppleScripts to be invoked automatically without first calling the Helper application. The AppleScripts would run as if they had been launched by the user, and could take the same actions as any AppleScript legitimately launched by the user. The AppleScript would have to already be present on the system; there is no way for an attacker to deliver an AppleScript of her choosing through this vulnerability. Mitigating Factors: ==================== Unchecked Buffer in HTML Element: - Successfully exploiting this issue with Office files requires that a user accept files from an unknown or untrusted source. Users should never accept files unknown or untrusted sources. Accepting files only from trusted sources can prevent attempts to exploit this issue. - A successful attack using HTML email would require specific knowledge of the user's mail client and cannot be mounted against PC users. - A successful attack using an HTML web page would require the attacker to lure the user to visiting a site under her control. Users who exercise caution in their browsing habits can potentially protect themselves from attempts to exploit this vulnerability. - On operating systems that enforce security on per-user basis, such as Mac OS X, the specific actions that an attacker's code can take would be limited to those allowed by the privileges of the user's account. Local AppleScript Invocation: - The vulnerability only affects IE on Mac OS 8 & 9. - A successful attack requires that the attacker know the full path and file name of any AppleScript they want to invoke. - The vulnerability provides no means to deliver an AppleScript of the attacker's construction: it can only invoke AppleScripts already present on the user's system. Risk Rating: ============ - Internet systems: None - Intranet systems: None - Client systems: Critical Patch Availability: =================== - A patch is available to fix this vulnerability. Please read the Security Bulletin at http://www.microsoft.com/technet/security/bulletin/ms02-019.asp for information on obtaining this patch. Acknowledgment: =============== - Josha Bronson of AngryPacket Security (http://sec.angrypacket.com/) and w00w00 (http://www.w00w00.org/). - --------------------------------------------------------------------- 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 7.1 iQEVAwUBPLxxfo0ZSRQxA/UrAQE1+Qf9FvSoqxdKNi+ItrLWFwonzQRJSBlYc71Q 2WnjCf2e4HeYf72oulucu9k3C+3FEfaduoHIUP+i/4ZHMRdkDicutwNcKxchhmzr KTNErbDtoBy7h6R5yFEH3BoDYYVfszYMEe9g1zSSVGVzuh0ns5NTOwWbIpkwyNwo lQD9J53VpvExf6dZYITt9cuWU/F19s22eIZgBWjmqimnJIzIOZ5/Hgi7Yu+JcvSi Xe+rL1JN+FGMdk8fmflgDYDxXM5v3WHJ1guKgDgNa1/kYUPZtUGE5uthXrJofckC C3y9HB58AzeGNCIZ4+3s3+nLpUy1tLtu3sIc3aGjkIysMIgEJIoWhA== =qrXG -----END PGP SIGNATURE----- ******************************************************************* You have received this e-mail bulletin as a result of your subscription to the Microsoft Product Security Notification Service. For more information on this service, please visit http://www.microsoft.com/technet/security/notify.asp. 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