Category: Writeups

Oregon State University Security Club

ångstromCTF Рstreams

Problem White noise is useful whether you are trying to sleep, relaxing, or concentrating on writing papers. Find some natural white noise here. Note: The flag is all lowercase and follows the standard format (e.g. actf{example_flag}) Author: ctfhaxor Points: 70 Hint: Are you sure that’s an mp4 file? What’s inside the file? Solution First, we…
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UTCTF 2019 – Scrambled

Tl;dr Cool encoding using Rubik’s cube, I wrote a Python script. This was a 1250 point Forensics challenge (highest points in the category). Here’s the description: By the time I took a look at the challenge, they had released a hint as well: Based on the hint, I quickly discovered that the challenge description described…
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UTCTF 2019 – Crackme

This was a 1200 point reversing challenge (tied for highest point value in the category). Here’s the description: This what we see when we run the binary: $ ./crackmePlease enter the correct password.>plsIncorrect password. utflag{wrong_password_btw_this_is_not_the_flag_and_if_you_submit_this_i_will_judge_you} Let’s take a look at the code in IDA Pro: Here’s what the decompilation shows: Read in 64 bytes from…
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UTCTF 2019 – Rogue Leader

Problem Description Our once-venerable president has committed the unspeakable crime of dine-and-dashing the pizza during our own club meetings. He’s on the run as we speak, but we’re not sure where he’s headed. Luckily, he forgot that we had planted a packet sniffer on his laptop, and we were able to retrieve the following capture…
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NSA Codebreaker 2018 – Task 7

Refunds – (Smart-Contract Development; Vulnerability Analysis; Exploit Development)

NSA Codebreaker 2018 – Task 6

Loophole – (Smart-Contract Development; Vulnerability Analysis; Exploit Development)

HITCON CTF 2018 – EV3 Basic

Link to GitHub Even though this was a pretty simple challenge, I really enjoyed it and wanted to do a write-up for it anyways. EV3 is the latest generation of the LEGO Mindstorms robots, and thanks to this challenge I know a lot more about the Mindstorms Communication and Firmware Developer Kits than I ever…
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