$ ctf42

zero_anonymity

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If only you had seen this coming...

After all, you were one of the pioneers that built cutting edge cryptography... made zero knowledge proofs practical!

But then the government turned those beautiful proofs against you. They built this horrendous system where every person first needs to authenticate themselves before they can connect to the Internet. And of course the government sits conveniently in the middle and watches everyone's traffic.

The worst of it all is that they're using your zk-SNARKs: every user authentication is a zero knowledge proof of the user's identity. Of course, they claim their system is super privacy preserving because nobody ever sends their secrets in network requests. But of course the government, which issues identities to people, knows exactly which hash maps to which user...

But there's one sliver of hope! Your buddy Mike built was the poor soul that the government forced to build this system. Your almost certain that he sneaked in a backdoor.

Unfortunately, Mike vanished before you could talk with him. Maybe he's in one of the labor camps to produce LLM training data. Or worse, he might not be producing any data at all anymore...

All the more important that you recover his backdoor and break free from this Orwellian surveillance!

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