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History of Computing

Challenge

One of the authors of IceCTF made this page but I don’t think it’s very accurate. Can you take hack it before the IceCTF team gets sued?

Solution

A blogging website with registration/login forms and comment submission

If we log in we get a cookie

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token:   eyJ0eXAiOiJKV1QiLCJhbGciOiJub25lIn0.eyJ1c2VybmFtZSI6InRlc3R1c2VyIiwiZmxhZyI6IkljZUNURntob3BlIHlvdSBkb24ndCB0aGluayB0aGlzIGlzIGEgcmVhbCBmbGFnfSJ9.
session: eyJ1c2VyIjozfQ.DnrHzA.T60QwnNSuvq2HH0VSnNqqzFZ-24

which base64 decode to:

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token: {"typ":"JWT","alg":"none"}.{"username":"testuser","flag":"IceCTF{hope you don't think this is a real flag}"}
session: {"user":3}.?.?

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