Mergy Dot Org Notes and Hacks From Jonathan Mergy

Tagstopping postfix attacks

Fixing the fail2ban filter for Postfix unverified address / user unknown spam attacks

For whatever reason, the default distributed postfix filter I had on my fail2ban setup on ubuntu was not triggering on: 450 4.1.1 Receipient address rejected: unverified address: unknown user mail.log errors. The failregex line was in there for it, but it wasn’t hitting on the endless dictionary attack random attempts from spammer servers across the world. This was annoying because, in...

Mergy Dot Org Notes and Hacks From Jonathan Mergy