Sarper (20)

Linear-feedback Shift Register Writeup - CTFlearn

This challenge is a cryptography challenge from CTFlearn. It’s a hard level challenge based on Linear-feedback Shift Register (LFSR). Hello! I have just implemented a super-cool PRNG! I've used every next generated by it number to XOR every next character in my super-secret message with.

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CyberLens Writeup - TryHackMe

CyberLens is an easy level boot2root machine available on TryHackMe. This box is a Windows machine with a vulnerable web application. The goal is to exploit the web application to get a reverse shell and then escalate privileges to get the root flag. As I…

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Cryptoversing Write-up - CTFLearn

Cryptoversing is a medium level reverse engineering challenge on CTFLearn. Basically, we are given a binary file and we need to find the flag somehow. Let’s start by running the binary file. sarp@IdeaPad:~/Desktop$ ./xor.bin [*] Hello! Welcome to our Program! Enter the password to contiune:…

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AudioEdit Writeup - CTFlearn 

AudioEdit is a hard web challenge on CTFlearn. That challenge is about exploiting SQL injection vulnerability in the metadata of an audio file. When we visit the website, we see a simple audio editing tool. We can upload an audio file, and then we can…

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BoilCTF Writeup - TryHackMe

BoilCTF is an annoying boot2root challenge on TryHackMe. It has a lot of rabbit holes! Definitely, easy-medium level challenge if the creator didn’t put those rabbit holes. As always, I started with a port scan: PORT STATE SERVICE REASON VERSION 21/tcp open ftp syn-ack vsftpd…

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