Windows Defender Exploit Guard ASR Rules for Office

On this blog post I continue looking at the ASR rules, this time I'm looking at the ASR rules for Office.  The ASR rules for office are:

  • Block Office applications from creating child processes
  • Block Office applications from creating executable content
  • Block Office applications from injecting code into other processes
  • Block Win32 API calls from Office macro

These rules only work on the following versions of Microsoft Office on Windows 10, version 1709 (and later) with Windows Defender configured with Real-Time protection enabled:

  • Microsoft Office 365
  • Microsoft Office 2016
  • Microsoft Office 2013
  • Microsoft Office 2010

Another thing to take in to account is that these controls only work with the following Office applications:

  • Microsoft Word
  • Microsoft Excel
  • Microsoft PowerPoint
  • Microsoft OneNote

for my testing I will use Word 2016 and Excel for my tests of the feature. 

Read More

Windows Defender Exploit Guard ASR VBScript/JS Rule

Microsoft has been adding to Windows 10 the features of the Enhanced Mitigation Experience Toolkit (EMET) in to the OS. On the 1709 release they added more features and expanded on them as part of Windows Defender Exploit Guard One of the features of great interest for me is Attack Surface Reduction. I have used this feature in EMET with great success as a mitigation to many techniques that abuse built in functionality in Windows. One of the rules of great interest to me is the "Block JavaScript or VBScript from launching downloaded executable content" rule. With the greater visibility now in Windows PowerShell many of us as going back to the old and tested Windows Scripting Host languages and old techniques that have worked for so long. 

Read More

Update to Pentest Metasploit Plugin

I recently update my Metasploit Pentest Plugin . I added 2 new commands to the plugin and fixed issues when printing information as a table. The update are small ones.

Lets take a look at the changes for the plugin. We can start by loading the plugin in a Metasploit Framework session.

Read More

Sysinternals Sysmon 6.10 Tracking of Permanent WMI Events

In my previous blog post I covered how Microsoft has enhanced WMI logging in the latest versions of their client and server operating systems. WMI Permanent event logging was also added in version 6.10 specific events for logging permanent event actions. The new events are:

  • Event ID 19: WmiEvent (WmiEventFilter activity detected). When a WMI event filter is registered, which is a method used by malware to execute, this event logs the WMI namespace, filter name and filter expression.
  • Event ID 20: WmiEvent (WmiEventConsumer activity detected). This event logs the registration of WMI consumers, recording the consumer name, log, and destination.
  • Event ID 21: WmiEvent (WmiEventConsumerToFilter activity detected). When a consumer binds to a filter, this event logs the consumer name and filter path

In version 6.10 it tracks the creation and deletion of __EventFilter Class, Any Consumer Type Class and __FilterToConsumerBinding Class. 

Read More

Basics of Tracking WMI Activity

WMI (Windows Management Instrumentation) has been part of the Windows Operating System since since Windows 2000 when it was included in the OS. The technology has been of great value to system administrators by providing ways to pull all types of information, configure components and take action based on state of several components of the OS. Due to this flexibility it has been abused by attackers that saw its potential since it early inclusion in the OS.

As security practitioners it is one of the technologies on Microsoft Windows that is of great importance to master. Until recently there was little to now logging of the actions one could take using WMI. Blue Teams where left leveraging third party tools or coding their own solution to cover gaps, this allowed for many year the abuse of WMI by Red Teams simulating the very actions that attackers of all kind have used in their day to day operation. We will take a look at how Microsoft improved the logging of WMI actions.

Read More