- Compare the values Return-Path and Mime From header. It supports SRS schemas and newsletters, too
- Detect the presence of an email in place of the name inside of Mime From header. Triggers only in case email is detected and differs from the value of name. Eg: "spoofed@email.example" real@sender.example
- Email::Address
- Email::Valid
Create plugins directory
mkdir /etc/mail/spamassassin/plugins/
and copy .pm files into it.
Enable plugins by copying vnet_plugins.cf into /etc/spamassassin/ or use your own file.
Be sure to check & tweak the score.
You can check the functionaluty by "cating" an email into spamassassing like:
cat youremail | spamassassin -D --lint 2>&1 | grep -i failed
Then find for terms like Spoof, FromNameIsSpoofedEmail or FromIsNotReturnPath
Enjoy!