“We should start a support group for Emotet fans affected by the takedown” I joked to a fellow security researcher earlier today. I obviously wasn’t a fan of Emotet — the malware was responsible for some really bad things — but I was nevertheless intrigued by it.

Today, a coordinated…


There are few things that I am really good at.

Phrased like that, it sounds like self-deprecation, but I actually think it is a valid judgement, especially when followed by the equally true statement: there are many things that I am quite good at.

Years ago, I was working as…


A German regional court recently forced secure email provider Tutanota to monitor a particular email account. Though this order has been called an encryption backdoor, it is not that: Tutanota is asked to monitor something they can see anyway, but aren’t necessarily looking at.

Still, it is a bit awkward…

Martijn Grooten

Cyber optimist. Researcher, reader, runner. Asker of difficult questions. Lapsed mathematician. Traveler in digital security. He/they.

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