What strategies should organisations follow to block malware attachments which continue to account for two-thirds of malware infections that result in data breaches?
Almost 25 years ago, the first ever email attachment was sent, using the new multipurpose internet mail extension (Mime) protocol. The technology spread like wildfire; and fast forward to now, around 200 billion email messages are sent daily. Many include attachments, from the modest logos in email signatures, through to stupidly large Microsoft Office files that people really should put on a USB stick and send in the post. It goes without saying that it’s easy for criminals to slip in a few malicious emails without being noticed.
The first real damaging email-bourne malware cases go back to 1999, with the Melissa, ILOVEYOU and Anna Kournikova worms. These were simple scripts, that when opened, would delete random files from user hard drives; and then email themselves to all contacts in the user’s address book. Further recipients were likely to trust the original sender; and as long as they were wondering why someone was smitten with them, or simply just liked pictures of tennis stars, then they too would open the attachment.