Monday, August 12, 2013
Today we released MS13-063 which includes a defense in depth change to address an exploitation technique that could be used to bypass two important platform mitigations: Address Space Layout Randomization (ASLR) and Data Execution Prevention (DEP). As we’ve described in the past, these mitigations play an important role in making it more difficult and costly for attackers to exploit vulnerabilities.
Wednesday, December 22, 2010
Today we released Security Advisory 2488013 to notify customers of a new publicly-disclosed vulnerability in Internet Explorer (IE). This vulnerability affects all versions of IE. Exploiting this vulnerability could lead to unauthorized remote code execution inside the iexplore.exe process. Proof-of-concept exploit bypasses ASLR and DEP The Metasploit project recently published an exploit for this vulnerability using a known technique to evade ASLR (Address Space Layout Randomization) and bypass DEP (Data Execution Prevention).
Wednesday, December 08, 2010
DEP (Data Execution Prevention) and ASLR (Address Space Layout Randomization) have proven themselves to be important and effective countermeasures against the types of exploits that we see in the wild today. Of course, any useful mitigation technology will attract scrutiny, and over the past year there has been an increasing amount of research and discussion on the subject of bypassing DEP and ASLR [1,2].
Wednesday, November 03, 2010
Today we released Security Advisory 2458511notifying customers of limited attacks leveraging an Internet Explorer vulnerability. The beta version of Internet Explorer 9 is not affected while Internet Explorer 6, 7, and 8 are affected. So far the attacks we have seen only target Internet Explorer versions 6 and 7 on Windows XP.
Wednesday, January 20, 2010
Yesterday we heard reports of a commercially available exploit that bypasses DEP. This exploit was made available to a limited number of major security vendors (Antivirus, IDS, and IPS vendors) and government CERT agencies. We wanted to use this opportunity to give an overview of current customer risk related to this DEP bypass.
Friday, January 15, 2010
Yesterday, the MSRC released Microsoft Security Advisory 979352 alerting customers to limited, sophisticated attacks targeting Internet Explorer 6 customers. Today, samples of that exploit were made publicly available. Before we get into the details I want to make one thing perfectly clear. The attacks we have seen to date, including the exploit released publicly, only affect customers using Internet Explorer 6.
Tuesday, September 08, 2009
This morning we released five security bulletins, all of them having a bulletin maximum severity rating of Critical and two having a bulletin maximum exploitability index rating of “1” (Consistent exploit code likely). We wanted to just say a few words about each bulletin to help you prioritize your deployment this month.
Tuesday, August 04, 2009
Over the past few months we have discussed a few different defense in depth mitigations (like GS [pt 1, pt2], SEHOP, and DEP [pt 1, pt 2]) which are designed to make it harder for attackers to successfully exploit memory safety vulnerabilities in software. In addition to the mitigations that we’ve discussed so far, a significant amount of effort has gone into hardening the Windows heap manager in order to complicate the exploitation of heap-based memory corruption vulnerabilities.
Friday, June 12, 2009
We have mentioned DEP in several recent blog posts (1, 2, 3, and 4). This blog post will answer: What is DEP? How can you enable DEP? What are the risks in enabling different modes of DEP? This is the first of a two-part blog series on DEP as a mitigation technology.
Friday, June 12, 2009
In our previous blog post, we explained how DEP works and how to determine if / how a process opted-in to DEP. Now we will demonstrate how DEP can be used to mitigate the risk of a real-world attack. We published a security advisory in February describing an Excel vulnerability in fully-patched Excel being used in limited targeted attacks.
