The firm said today that spam is now accounting for over 85 per cent of all email traffic in the UK, and that much of this is due to the inventiveness of the senders.
The attacks, Cloudmark said, take a variety of forms, but most involve the manipulation of text, images, or URLs.
“As spam filters get smarter and more accurate, we are seeing spammers get craftier in their attacks," said Neil Cook, vice president, technology services at Cloudmark.
"The over-the-top and in some cases, almost amusing, lengths spammers are taking in their attempts to bypass spam filters really showcase their desperation,” he said.
Examples offered by the firm include spammers disguising their campaigns as images, or using repeated small text to spell out one larger word.