Security Research & Defense | Microsoft Security Response Center

MS11-034: Addressing vulnerabilities in the win32k subsystem

Tuesday, April 12, 2011

Today we released security bulletin MS11-034 to address vulnerabilities in the win32k subsystem. This update addresses externally reported issues as well as several internally found vulnerabilities that were discovered as part of our variant investigation. The bulletin may appear to address an alarmingly large number of issues. However, if you dig into the issues themselves, you’ll find that the 30 vulnerabilities addressed in this update really just share three separate vulnerability root causes: insufficient validation or locking of win32k objects after a user-mode callback.

Blocking Exploit Attempts of the Recent Flash 0-Day

Thursday, March 17, 2011

We’ve recently become aware of a new exploit in the wild targeting a 0-day vulnerability in Adobe Flash Player. This exploit differs from the typical Flash Player attacks we’ve seen where a victim is lured into browsing to a website hosting malicious Flash content. Instead, these attacks involve a malicious Flash .

Notes on exploitability of the recent Windows BROWSER protocol issue

Wednesday, February 16, 2011

Earlier this week a PoC exploit for a vulnerability in the BROWSER protocol was released on Full Disclosure. There has been some discussion regarding whether this issue can result in Remote Code Execution (RCE) or is only a Denial of Service (DoS). This blog post provides details on the exploitability based on our internal analysis.

Additional Fixes in Microsoft Security Bulletins

Monday, February 14, 2011

From time to time we receive questions regarding fixes not documented in security bulletins. Some call these “silent fixes.” We hope this blog post answers those questions and helps clarify Microsoft’s process in fixing and documenting all vulnerabilities and addressing internally discovered variants. It’s important to remember the following: As part of Microsoft’s comprehensive security update process, Microsoft will address variants of reported issues.

Assessing the risk of the February security updates

Tuesday, February 08, 2011

Today we released twelve security bulletins. Three have a maximum severity rating of Critical and nine have a maximum severity rating of Important. This release addresses three publicly disclosed vulnerabilities. We hope that the table below helps you prioritize the deployment of the updates appropriately for your environment. Bulletin Most likely attack vector Max Bulletin Severity Max Exploit-ability Likely first 30 days impact Platform mitigations and key notes MS11-003(IE) Victim browses to a malicious webpage.

Regarding MS11-004, Addressing an IIS FTP Services Vulnerability

Tuesday, February 08, 2011

Today we released MS11-004 to address a vulnerability in the Microsoft FTP service an optional component of Internet Information Services (IIS). In this blog, we would like to cover some additional technical details of this vulnerability. First, we want to clarify that the vulnerability lies in the FTP service component of IIS.

More information about the MHTML Script Injection vulnerability

Friday, January 28, 2011

Today we released Security Advisory 2501696 to alert customers to a publicly disclosed vulnerability in the MHTML protocol handler. This vulnerability could allow attackers to construct malicious links pointing to HTML documents that, when clicked, would render the targeted document and reflected script in the security context of the user and target location.

New workaround included in Security Advisory 2488013

Tuesday, January 11, 2011

We have just updated Security Advisory 2488013 for the publicly-disclosed Internet Explorer CSS vulnerability. It now reflects the fact that limited attacks attempting to exploit this vulnerability are present in-the-wild. The advisory also includes a new workaround that can help protect your computers until a security update is available. This workaround is different from the workarounds that we typically recommend, and so we wanted to give you more detail about it here.

Assessing the risk of public issues currently being tracked by the MSRC

Friday, January 07, 2011

At Microsoft, as at most large software vendors, we are likely to have publicly known issues under investigation at any given time. This is what we do on the Security Research & Defense team. Recently we’ve seen confusion from folks trying to make sense of some of the current public issues.

Assessing an IIS FTP 7.5 Unauthenticated Denial of Service Vulnerability

Wednesday, December 22, 2010

There has been some discussion around a publicly posted PoC code that exploits a vulnerability in IIS FTP 7.5, which ships with Windows 7 and Windows Server 2008 R2. Our engineering team is looking into the situation and has made a few preliminary observations that might clear up some confusion. We’ve observed three notable characteristics.

IIS FTP IAC Interpret As Command