March 2016 Patch Tuesday

March’s Patch Tuesday includes five Critical and eight Important bulletins addressing a total of 43 vulnerabilities. Internet Explorer receives its monthly dose of security fixes, however, Edge seems to be following close behind with a whopping 11 vulnerabilities being patched. Additionally, many elevation of privilege and security feature bypasses are addressed, the most interesting perhaps is for a potential USB flash drive attack in MS16-033.

MS16-023: Cumulative Security Update for Internet Explorer (3142015)

Starting off this Patch Tuesday, Internet Explorer is patched for 13 critical remote code execution vulnerabilities, caused by memory corruption due to improperly handling objects in memory. To exploit these, an attacker would likely host a malicious website and entice the victim to browse to it.

MS16-024: Cumulative Security Update for Microsoft Edge (3142019)

Edge is patched again this month for one information disclosure and ten memory corruption vulnerabilities which can allow a remote attacker to execute arbitrary code. As was the case with IE, a typical attack scenario would involve an attacker hosting a malicious website, although another potential attack vector is through web-advertising (malvertising).

MS16-025: Security Update for Windows Library Loading to Address Remote Code Execution (3140709)

Another DLL Hijacking vulnerability is addressed in Windows which can allow arbitrary code to be ran in the context of the current user. Successful exploitation requires an attacker to already have access to the filesystem and planting a malicious DLL within the directory of the affected application.

MS16-026: Security Update for Graphic Fonts to Address Remote Code Execution (3143148)

Font parsing strikes again this month offering up one denial of service and one remote code execution vulnerability. These issues exist due to Windows Adobe Type Manager Library improperly handling OpenType fonts and typical attack vectors involve malicious documents or webpages in which they are embedded into. Windows 10 provides some extra protection, however, because it can limit code execution to an AppContainer sandbox context with limited privileges and capabilities.

MS16-027: Security Update for Windows Media to Address Remote Code Execution (3143146)

This bulletin resolves two critical vulnerabilities within Windows Media Player which can lead to remote code execution. An attacker could entice their victim to view specially crafted media content through a website or via email attachments.

MS16-028: Security Update for Microsoft Windows PDF Library to Address Remote Code Execution (3143081)

Windows PDF Library is back with two remote code execution vulnerabilities which occur when opening a specially crafted pdf file. Only systems running Windows 8.1 and above (including Windows 10) are affected.

MS16-029: Security Update for Microsoft Office to Address Remote Code Execution - Important (3141806)

And what is a Patch Tuesday without our dear friend Microsoft Office? This month brings only one security feature bypass and two memory corruption vulnerabilities. The security bypass is due to an invalidly signed binary which an attacker could take advantage of by crafting a similarly configured binary to host malicious code. The two memory corruption vulnerabilities can potentially allow remote code execution upon opening specially crafted documents.

MS16-030: Security Update for Windows OLE to Address Remote Code Execution (3143136)

This bulletin resolves two remote code execution vulnerabilities within Windows OLE that affect all systems from Vista and above. These issues arise from OLE not properly validating user input and can be exploited through the three most common attack vectors – opening files, viewing emails, and visiting websites.

MS16-031: Security Update for Microsoft Windows to Address Elevation of Privilege (3140410)

Windows itself is patched for an elevation of privilege vulnerability stemming from improper validation and enforcement of impersonation levels. Exploitation requires an attacker to have valid credentialed access to the system where they would run a specially crafted application to raise their privileges. Windows 8.1 and above systems are not affected, limiting the target scope for this vulnerability.

MS16-032: Security Update for Secondary Logon to Address Elevation of Privilege (3143141)

This bulletin addresses an elevation of privilege vulnerability, however, this one affects all systems from Vista and above. The issue lies within the Secondary Logon Service which fails to properly manage request handles in memory.

MS16-033: Security Update for Windows USB Mass Storage Class Driver to Address Elevation of Privilege (3143142)

The USB flash drive attack vector makes an appearance this month with an elevation of privilege vulnerability within the Windows USB Mass Storage Class Driver. Exploitation requires credentialed as well as physical access to the system and can be achieved when inserting a USB drive into the machine.

MS16-034: Security Update for Windows Kernel-Mode Drivers to Address Elevation of Privilege (3143145)

Windows’ Kernel Mode Drivers fall victim to more abuse with this bulletin addressing four elevation of privilege vulnerabilities. Similar to the previous EoP bulletins, these vulnerabilities require credentialed access to the system in which an attacker would run a specially crafted program to take control of the entire system.

MS16-035: Security Update for .NET Framework to Address Security Feature Bypass (3141780)

Finally, the beloved .NET framework is patched for a security feature bypass which is caused by improper validation on certain elements of a signed XML document. An attacker could exploit this to modify an XML document with arbitrary data, without invalidating the associated signature.