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Note: WM indicates a Word macro virus. XM indicates an Excel macro virus.

General Overview: Word Macro Virus Family

The Word Macro family of viruses use the WordBasic macro language to infect and replicate in and among MS Word documents and templates. Most notably, this new family of viruses is platform independent - they will infect documents and templates on DOS, Macintosh, Windows 3.x, Windows 95 and Windows NT operating systems.

These viruses use several of the features of the MS Word "environment" to auto-execute viral macro code. Once an infected document is opened and the virus launched, generally, the virus will infect the user's NORMAL.DOT template. This template is the basis for the majority of other documents and templates and is globally available to all other MS Word templates on the system. Once entrenched in the NORMAL.DOT file, the virus will spread to all other documents and templates as they are opened. Note that, by default, the NORMAL.DOT template is the first document opened when you launch MS Word without specifying a different document on the command line. This will immediately put the virus in control every time you launch MS Word.

Word Macro viruses force documents to be saved as MS Word templates, despite what the name or extension of the document file might be recorded as. Forcing documents to be saved as templates is used as a means of propagation as macros are not saved in standard .DOC files. Only templates can contain any actual macro code and therefore be used as a carrier.