Category: Writeups

Oregon State University Security Club

DefCon Qualifiers 2019 – redacted-puzzle

Solving redacted-puzzle from DefCon Qualifiers 2019

ångstromCTF – lithp

Solving a lisp challenge with no actual understanding of lisp.

ångstromCTF – streams

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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