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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Maldoc drops DLL and executes via ExecuteExcel4Macro

Behavioral information is a key indicator used to determine if an office document is malicious or not. I’ve recently seen a series of malicious office documents that lacked any observable process behavior – such as the execution of Powershell or JavaScript via cscript/wscript. As I began looking into this document, it became apparent why – it was using ExecuteExcel4Macro to load and execute a hidden DLL. Looking at the Macros Using Oledump, several macro streams where identified in this document (17 – 20, 23 – 24). Additionally, it contains a stream OLE 1.0 embedded data (see stream 4 above). This…

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