The latest update US CERT Cybertip covers antivirus software. As always, the tip sheet explains the basics in simple language, aiming at a non-technical audience. It is covered by a copyright license stating "You are permitted to reproduce and distribute documents on this web site in whole or in part, without changing the text you use, provided that you include the copyright statement or "produced by" statement and use the document for noncommercial or internal purposes.", in other words you can reproduce and distribute it within your organization with attribution to CERT but you (and we!) may not sell it on.
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