Why you should delete .doc .xls or .ppt files


If we’ve said it once, we’ve said it a thousand times … ignore or delete any .DOC .XLS .PPT files you get via email or shared.

The main carrier of virus infection is Microsoft Office documents, a fact that Microsoft doesn’t like to talk about.

What Microsoft doesn’t say is that the major source of infection are the ‘old’ Office documents – .doc  .xls .ppt etc.

The ‘new’ (Office 2007 and later) formats .docx .xlsx and .pptx are much safer and much less likely to contain nasties.  We don’t know why Microsoft doesn’t make more of this advantage.

Too often, Microsoft and others talk about a ‘malicious Word document’ without making the important distinction between a .doc and .docx .  In most cases the virus is contained in a .doc file but the regular user isn’t told that.

We still call .docx etc ‘new’ Office formats but they are over ten years old.  Any Microsoft Office from 2007 onwards uses the new formats by default.  Only people with quite old versions of Office should be regularly using .doc files, let along sharing .doc with others.

Just this week there’s an example of how .doc files are a worry.

Sanny comes again

The SANNY virus has been around since 2012 but Fireeye is reporting a SANNY revival with new ways to infect Windows 10 and trick people into authorizing admin access to the computer.

There are various documents going around, one in Russian another in English.  They are all .doc files.

This particular infection seems to be targeting diplomatic organizations with documents in English and Russian.

Trust no .doc .xls or .ppt documents

Our advice is to treat any .doc .xls or .ppt files with great suspicion.  Don’t open them.

If they come from someone you know, politely ask them to resend in a safer, and smaller, format.


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