“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 action seriously disrupted the malware operation. I’ll leave it for future historians to decide whether the term “the world’s most dangerous malware” was justified and whether Europol was right to use the past tense in its infographic, but this was good work. Congrats to all those involved. …


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 an academic researcher in pure mathematics. It was making me really unhappy, so I ended up doing a lot of other things on the side, both at the university and in my spare time. …


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: one important reason to use encryption is that you don’t even have to worry about court orders, because they can’t break the unbreakable. …

Martijn Grooten

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

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