WordPress Popunder Malware Redirects to Scam Sites

Over the last year we’ve seen an ongoing malware infection which redirects website visitors to scam sites. So far this year our monitoring has detected over 3,000 websites infected with this injection this year and over 17,000 in total since we first detected it in March of 2021.

The reported behaviour is always the same: After a few seconds of loading, the website will redirect to a dodgy scam site.

Checking the Payload

The malware is always injected into the active theme’s footer.php file, and contains obfuscated JavaScript after a long series of empty lines, no doubt trying to…