Instead of simply discarding incoming phishing emails from APT actors, I decided to make sure it was loud and clear in mail logs that I discarded them - with attribution.
All tagged sendmail
Fail2ban for Sendmail AUTH
Mail server admins always notice when spammers try to use an AUTH command to try to relay spam through a mail server. But when they start hammering away with a much more sophisticated botnet, things start to get serious - especially for the paranoid.
Server Upgrades
Upgrading the operating system of a server can be easy, and it can be painful. I upgraded four of them, and as only three had issues, I consider myself lucky. Nonetheless, this wasn't easy.
MTA-STS: Why and How I Did It
I closed a security hole on my mail server. Granted, one could barely see the hole, and the chances of compromise are quite low, but everything counts. Right? Right?
Blast from the Past: Two Bugs, One Email
The original story behind an old bug. An interesting look into bug hunting almost two decades ago.
Talon
There are reasons I run my own mail server, they may seem paranoid but they are not. Well. not too paranoid...
Server Error
It's Friday afternoon, and one console error message can ruin the entire day.
Researcher's Plight: Sendmail
Security research is a lot of fun. Except when a bunch of people complain.