Internet Explorer (IE)

MS09-014: Addressing the Safari Carpet Bomb vulnerability

Following up on Security Advisory 953818, today we released MS09-014, rated as Moderate, which addresses aspects of the Safari Carpet Bomb vulnerability. On a Windows operating system this vulnerability allows an attacker, through Safari, to drop arbitrary files on a user’s desktop. As of Safari 3.1.2 Apple has removed this behavior from Safari. Why is …

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Released build of Internet Explorer 8 blocks Dowd/Sotirov ASLR+DEP .NET bypass

Last summer at BlackHat Vegas, Alexander Sotirov and Mark Dowd outlined several clever ways to bypass the Windows Vista defense-in-depth protection combination of DEP and ASLR in attacks targeting Internet Explorer. One approach they presented allowed attackers to use .NET framework DLL’s to allocate executable pages of memory at predictable locations within the iexplore.exe process. …

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Behavior of ActiveX controls embedded in Office documents

The Microsoft Office applications (Word, Excel, PowerPoint, etc) have built-in ActiveX control support. ActiveX support allows a richer experience when interacting with an Office document. For example, a document author could use the Safe-For-Initialization Office Web Components (OWC) ActiveX control to retrieve data from an intranet data source. Office applications’ prompting behavior By default, Office …

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Stack overflow (stack exhaustion) not the same as stack buffer overflow

Periodically we get reports into the MSRC of stack exhaustion in client-side applications such as Internet Explorer, Word, etc. These are valid stability bugs that, fortunately, do not lead to an exploitable condition by itself (no potential for elevation of privilege). We wanted to clarify the distinction between stack exhaustion and stack buffer overflow. Stack …

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Clarification on the various workarounds from the recent IE advisory

Today Microsoft revised the Workarounds section of Security Advisory 961051. We wanted to share more detail about the vulnerability and explain the additional workarounds here to help you protect your computers. Information about the vulnerability The vulnerability is caused by memory corruption resulting from the way Internet Explorer handles DHTML Data Bindings. This affects all currently supported …

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IE 8 XSS Filter Architecture / Implementation

Recently we announced the Internet Explorer 8 XSS Filter and talked a bit about its design philosophy. This post will describe the filter’s architecture and implementation in more detail. Design Goals The Internet Explorer 8 XSS Filter is intended to mitigate reflected / “Type-1” XSS vulnerabilities in a way that does not “break the web.” …

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MS08-050 : Locking an ActiveX control to specific applications.

MS08-050 concerns an ActiveX control that can be maliciously scripted to leak out personal information such as email addresses. There appeared to be no need for the control to have this behaviour so giving it a Kill-Bit seemed the correct approach to take. During the extensive testing that each security update undergoes, however, it became apparent …

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