Category: CTF
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Angstrom Rev Writeups
I’ve decided to fully focus on Rev and Web for CTFs now, as I find Pwning too magical, and not really “useful” to me. Anyhoo, here are some reversing writeups from Angstrom CTF! Dyn Running the code, we see that it gets the flag as an input Stepping through the code, it tries to unwrap 32 characters, […]
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247CTF
Here are some writeups for 247CTF, which are mostly web challenges. ACID We’re given a page that has two accounts. You can transfer funds between the two accounts with the parameter ?to=1&from=2&amount=1 To get the flag, you require more than the total available funds at the start, which is 247. If we transfer the funds […]
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Midnight Sun CTF Gambler
This is one of the hardest CTF I’ve been in. My team did really well to qualify for the finals in Sweden, and I wish them all the best as I will not be joining them. The Gambler This was a DotNet binary, we so could use DNSpy to inspect the full source code In […]
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Winja CTF Reverse Engineering
Honestly, this was a very easy CTF rev challenge. One of them had a flaw with there being more than 1 possible flag, while another was straight out leaking the whole flag with ltrace. So this is the only writeup worth writing, even though it was extremely easy Matriarcado Opening the binary, we see that […]
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WolvSec CTF: pwning canaries
Another writeup for a pwn CTF challenge! In this challenge, we need to leak the canary value via format strings, and do a buffer overflow to change the return address to the desired function. The buffer for us to overflow is 16 characters long. It first reads in data with a format string, and prints […]
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WolvSec CTF
I briefly participated in a CTF hosted by WolvSec here: https://ctf.wolvseccon.org/. This post is going to be looking at a “Medium” level difficulty Reverse Engineering problem! n33dl3 When we run the file, it prints a single statement, before terminating Firing this binary in Ghidra, we see a deep level of nested function calls, however, they […]