It's one of the reasons why text messages have been deprecated as an out-of-band form of second factor authentication in the latest NIST draft, he said.
Cloudmark also reported that two small countries, Vietnam and Bangladesh, were starting to make a big splash when it comes to spam.
Email sent from Vietnam and Bangladesh to mailboxes protected by Cloudmark were 66 percent and 59 percent spam, respectively, according to the company's report. The U.S. and other wealthier nations were top targets.
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