This August Microsoft has released nine security bulletins which account for a whole variety of critical vulnerabilities. The most critical bulletins are MS14-051 (Internet Explorer), MS14-045 (Kernel-mode), and MS14-049 (Windows Installer).
MS14-043 fixes a critical code execution vulnerability within Windows Media Center (people still use that?). The vulnerability itself is specifically within a COM object called MCPlayer.dll which when exploited can allow for code execution with the same privilege as the user that opens a malicious file via email or web. For those Vista users out there you dodge this bullet and that might be the best thing Vista has given you in a long time.
MS14-044 fixes two different SQL vulnerabilities with one being a XSS attack and the second a denial of service. In this case however the XSS seems to win out as it actually can be leveraged by an attacker to take any action a user could take on a site on behalf of the targeted user. But even that is not as scary as it sounds given in Internet Explorer 8-11 the XSS filter prevents this attack when launched from Internet zone (internet websites). The filter does not however apply to attacks launched against your Intranet zone (internal websites). That being said we suggest enabling the XSS filter for Intranet zone also and if you head on over to the Microsoft bulletin you will find some Workaround suggestions for just that.
MS14-045 includes fixes for Kernel-Mode Drivers which can lead to an Elevation of Privilege. And if that sounds like a broken record then you are right. This patch Tuesday continues with a now long traditional of critical kernel driver vulnerabilities that an attacker can use to elevate their privileges from any regular user to kernel code execution. This vulnerability is of course made even more serious when paired with a remote client-side application vulnerability which would typically lead to code execution as the logged in user but combined with this would result in kernel execution of code.
MS14-046 fixes an interesting vulnerability that can result in the bypassing of Microsoft’s ASLR (Address Space Layout Randomization). This is an important operating system mitigation to vulnerability exploitation and will probably be leveraged in the future when combined with other exploits. Most versions of .NET are affected with the exception of Windows RT, Windows RT 8.1, .NET Framework 3.5 Service Pack 1, .NET Framework 4, .NET Framework 4.5, .NET Framework 4.5.1, and .NET Framework 4.5.2. This vulnerability is probably a great reminder to go check out Microsoft’s EMET (Enhanced Mitigation Experience Toolkit) if you have not already.
MS14-047 brings another bypass for ASLR this time by leveraging a vulnerability within LRPC (Local RPC). There are no mitigations for this vulnerability and even EMET will not bring any relief. This will be another good patch to get rolled out as it makes exploitation of other vulnerabilities easier.
MS14-048 will make you take note with a fix for Microsoft’s OneNote. But bad jokes aside this vulnerability can allow for remote code execution if a specifically crafted file is opened within OneNote. This like most client-side attacks will allow for code execution with the same privileged as the logged on user. Which means hopefully you have implemented least-privilege and do not have your users running around wild with local administrator privileges. There have not been many OneNote vulnerabilities in the past – but maybe that is because no one was looking?
MS14-049 fixes a vulnerability within Windows Installer that can lead to elevation of privileges. The vulnerability specifically is triggered by a local attacker triggering an issue within how Windows Installer handles repairs of previously installed applications. This can lead to an attacker running code in kernel mode. This is another vulnerability that attackers can pair with a client-side attack to go from a standard user account to running code as kernel.
MS14-051 brings back the pain for every version of Internet Explorer. We wondered last month if that might be the last major vulnerability update for Internet Explorer for a while and now we know. MS14-043 fixes one publicly disclosed vulnerability and twenty-five privately reported vulnerabilities. And of course this means remote code execution to compromise systems. This constant slew of critical Internet Explorer vulnerabilities is yet another reminder of the importance of implementing least-privilege to make sure that if a user is exploited with one of these vulnerabilities the attacker will not simply be handed Administrator rights.