H4CK1NG G00GL3 - Ep 005 Ch 002: Project Zero Adventure

Bleichenbacher strikes back again (and again).
H4CK1NG G00GL3 - Ep 005 Ch 002: Project Zero Adventure

HACKING GOOGLE is a documentary of Google’s cybersecurity teams and H4CK1NG G00GL3 is it’s CTF counterpart. Project Zero Adventure is a cryptography challenge I wrote.

In the game, the players control the Security Princess to dodge the obstacles and catch the bugs (a variant of Google Chrome’s dinosaur game). After that, the server will sign messages consisting of the players' name and the score via the /sign API. The players will then submit it to the /highscore API. If the score submitted to the highscore API is negative, they will be given the flag.

However, there is one catch: The server is only willing to sign the results with non-negative scores.

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DiceCTF 2022 (I): commitment-issues

DiceCTF 2022 (I): commitment-issues

DiceCTF is an annual CTF competition prepared by @dicegangctf. The challenges are great and we had a lot of fun solving them. I might be compiling writeup for a number of them, which depends if I had time.

I will first cover on a crypto challenge called commitment-issues, which had 16 solves (out of 1127 participating teams). @grhkm2023 and I spent a good 3 to 4 hours working on this challenge.

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justCTF 2020: Oracles

justCTF 2020: Oracles
I was playing justCTF 2020 with the new CTFers in Yakitori (Firebird). Oracles is a fun cryptography challenge that I solved during the game, and I thought this is worth compiling the write-up.
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