Hi,
For some reason your server is not able to fetch the following URL from our scanning servers:
https://noc1.wordfence.com/malwarePrefixes.bin
or
https://noc1.wordfence.com/malwarePrefixes.bin
This is a file that’s regularly updated with malware signatures. You can ask your hosting provider to try to investigate why your server is unable to fetch this file.
The plugin tries to fetch this file, then once fetched, does a modulus 4 on the length of the file and expects zero as the result. It’s a light integrity check and it’s that check that is failing – so the file comes back with the wrong length. I’ve just verified that the file is the correct length on our servers by manually downloading it.
You can stop the error from happening by disabling the following scan on your options page: “Scan for signatures of known malicious file”.
But I’d suggest you ask your hosting provider to find out why your server is unable to download that file.
Regards,
Mark.