Friday, March 20, 2009
In a previous post we noted some stack-based vulnerabilities, such as MS08-067, that GS was not designed to mitigate due to the degree of control available to an attacker. However, other vulnerabilities such as the ANI parsing vulnerability in MS07-017 would have been mitigated if the GS cookie protection had been applied more broadly.
Monday, March 16, 2009
The Microsoft C/C++ compiler supports the GS switch which aims to detect stack buffer overruns at runtime and terminate the process, thus in most cases preventing an attacker from gaining control of the vulnerable machine. This post will not go into detail about how GS works, so it may be helpful to refer to these MSDN articles for an overview and loads of detail on how GS works and what a GS cookie is.
Friday, March 13, 2009
After releasing security update MS09-008, we received a number of questions on the WPAD issue (CVE-2009-0093) addressed in the update. There are claims that this update is ineffective. Let me be clear that this update will protect you and it should be deployed as soon as possible. Below is an overview on how the complete security update helps protect a system.
Tuesday, March 10, 2009
MS09-007 resolves an issue in which an attacker may be able to log onto an SSL protected server which is configured to use certificate based client authentication with only the public key component of a certificate, not the associated private key. Only a subset of customers who log into SSL protected servers are at risk but it is a little tricky to explain who might be affected due to the unique nature of this vulnerability.
Thursday, March 05, 2009
It’s getting busy around here with people preparing for the CanSecWest security conference (http://cansecwest.com/). Many of the Microsoft Security Engineering Center (MSEC) and Microsoft Security Response Center (MSRC) members that regularly post to this blog will be attending CanSecWest and soaking up the 3 days of presentations & networking. If you haven’t heard us talk about the Security Science angle of MSEC before, let me explain.
Tuesday, March 03, 2009
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
Tuesday, February 24, 2009
This morning, we posted Security Advisory 968272 notifying of a new Excel binary file format vulnerability being exploited in targeted attacks. We wanted to share more information about the vulnerability to help you assess risk and protect your environment. Office 2007 being targeted The current attacks we have seen target users of Office 2007 running an earlier version of Windows (Windows 2000, XP, 2003).
Monday, February 02, 2009
The original Security Vulnerability Research & Defense (SVRD) blog was launched in 2007, with the intent of providing more information about vulnerabilities in Microsoft software, mitigations and workarounds and active attacks. The blog is now expanding its focus a bit (and changing its name slightly), to include postings contributed by the Microsoft Security Engineering Center (MSEC) Security Science team.
Monday, February 02, 2009
One of the responsibilities of Microsoft’s Security Engineering Center is to investigate defense in depth techniques that can be used to make it harder for attackers to successfully exploit a software vulnerability. These techniques are commonly referred to as exploit mitigations and have been delivered to users in the form of features like /GS, Data Execution Prevention (DEP), and Address Space Layout Randomization (ASLR).
Friday, January 30, 2009
On MondayIE8 RC1 was released. Here are some of the most interesting improvements and bug fixes to the XSS Filter feature: Some byte sequences enabled the filter to be bypassed, depending on system locale URLs containing certain byte sequences bypassed the Beta 2 filter implementation in some locales. For example, with a Chinese locale system, URLs of the following format would bypass the filter:
