Maldoc uses template injection for macro execution

I recently came across a handful of malicious office documents (maldocs) whose network traffic struck me as a slightly odd. As you can see in the screenshot below, there are several HTTP requests to the hxxp://moveis-schuster-com.[ga] domain and some of these requests appear to be for a DOTM file. A DOTM file is a macro-enabled office template file, so I dug in a bit more. As is typical in my workflow, I first inspected the document using oledump – no macros. This is no surprise as the HTTP traffic would indicate that the macros come later. My next step was…

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Reversing Control Structures with Ghidra: Loops

In this video we’ll take a look at several basic looping structures in a C program, compile from source and reverse them using Ghidra. Our goals will be to analyze the resulting program flow using both the listing view (disassembly) and the decompiler, identify key logic and discuss the underlying assembly instructions. Understanding basic control structures is one of the first steps in developing key reverse engineering skills. The source code for the sample program can be found on my Github: https://github.com/jstrosch/learning-reverse-engineering/tree/master/Control%20Structures

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Getting Started Reversing C++ Objects with Ghidra (Part 1)

In this video we’ll take a look at several sample programs that use C++ objects, compile them from source and then reverse engineer them with Ghidra. Our goals will be to identify when the objects are created, recognize the size/structure of the memory allocation and how it’s used by the object and explore the use of virtual functions and virtual function tables. Recognizing the use of C++ objects is helpful a variety of reverse engineering activities, to include malware analysis and software exploitation. This will be the first in a series of videos exploring the reverse engineering of object-oriented languages….

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Reversing Basic C++ Objects with Ghidra: Inheritance and Polymorphism (Part 2)

In this video we’ll take a look at several sample programs that use C++ objects, compile them from source and then reverse engineer them with Ghidra. Our goals will be to identify the size/structure of the memory allocation and how it’s used by the object and explore the use of virtual functions and virtual function tables, inheritance and polymorphic behavior. Recognizing the use of C++ objects is helpful a variety of reverse engineering activities, to include malware analysis and software exploitation. This is the second video in a series exploring the reverse engineering of object-oriented languages. Source code can be…

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Excel 4 Macros – Get.Workspace Reference

With the recent resurgence of the use of Excel 4 macros in malicious excel documents, I’ve found myself scouring the internet looking for language references. One such function that was particularly difficult to find documentation for was Get.Workspace, which takes a integer value as an argument and returns information about the environment. Since it appears that it is all but impossible to find Excel 4 macro documentation from Microsoft, I thought I’d create a few posts in the hopes of the content getting indexed and thus easier to find. The source of this information came from this PDF, which used…

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