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j3rry

j3rry
Bugcrowd Student Finale CTF 2025 Writeup:  MadDog Memorial

Bugcrowd Student Finale CTF 2025 Writeup: MadDog Memorial

Here, I had to find a way to get the admin flag from a memorial website. The site assigns regular visitors random usernames, but the flag is restricted to admins only. I needed to figure out how to trick the system into believing I was the administrator.

By j3rry Nov 25, 2025
Bugcrowd Student Finale CTF 2025 Writeup:  Predictable

Bugcrowd Student Finale CTF 2025 Writeup: Predictable

In this chal, I was given a compromising an admin account on a website. I had to figure out how password reset tokens were generated and create a valid one to hijack the account. The hint suggested that the tokens were generated using predictable patterns based on timestamps and email addresses.

By j3rry Nov 25, 2025
CrateCTF 2025 Writeup: Fiats och Shamirs Skyltsmedja

CrateCTF 2025 Writeup: Fiats och Shamirs Skyltsmedja

In this challenge, we visited a "Sign Smith" shop that used a fancy cryptographic protocol to verify customers. Our goal was to forge a signature to prove we were allowed to pick up the flag, even though the shop refused to sign any message containing the word "flag."

By j3rry Nov 25, 2025
CrateCTF 2025 Writeup: Evenemang

CrateCTF 2025 Writeup: Evenemang

The is a forensics challenge where a user accidentally ran a mal program hidden among 1000 other numbered programs (1.exe to 1000.exe) in a folder on their desktop. Instead of manually checking each program, they ran all of them and captured the system logs to analyze which one behaved suspiciously.

By j3rry Nov 25, 2025
CrateCTF 2025 Writeup: Den buslätta utmaningen

CrateCTF 2025 Writeup: Den buslätta utmaningen

"Buslätt" is a OSINT challenge that is Swedish for "very easy." It gives you with a logo, a compass pointing South-West, and a text box. While the text claims "you will solve it easily". The goal is to use visual analysis of the sign's logo & the compass direction to get the true location in Sweden.

By j3rry Nov 25, 2025
CrateCTF 2025 Writeup: Skicka vidare

CrateCTF 2025 Writeup: Skicka vidare

In this challenge, we were given two mysterious files and a server address. The goal was to find a flag hidden on that server. The catch? We didn't have a password, and the server was listening on a weird, non-standard port.

By j3rry Nov 25, 2025
Enigma Xplore3.0 Writeup - Bored Waiting

Enigma Xplore3.0 Writeup - Bored Waiting

This is an OSINT challenge wherein we had to guess the location and time of the video provided in the challenge. The flag format: EnXP{time_location}

By j3rry Nov 25, 2025
BSidesNYC CTFd Writeup - Hacky Bird

BSidesNYC CTFd Writeup - Hacky Bird

It was a web challenge where in the flag will be received when the score reaches 1 million in the flappy bird game...!!!

By j3rry Nov 25, 2025
BSidesNYC CTFd Writeup - Rush

BSidesNYC CTFd Writeup - Rush

It was a misc. multi-stage CTF challenge themed around the band Rush. Each stage required a combination of decoding, thematic analysis, and logical deduction.

By j3rry Nov 25, 2025
BSidesNYC CTFd Writeup - BASEic Encoding

BSidesNYC CTFd Writeup - BASEic Encoding

This document outlines the steps to solve the "BASEic Encoding" challenge, which involves decoding a string of complex Unicode characters to reveal the flag. Challenge String: ꍦ鱡𓍻普散桤鵟ꌰ橤𓅟頳桲𓄷敟鑦鵴樱靟樴𠌳

By j3rry Nov 25, 2025
BSidesNYC CTFd Writeup - Secure

BSidesNYC CTFd Writeup - Secure

The objective is to find a hidden flag by exploiting a common cloud security misconfiguration: exposed credentials in publicly accessible source code. The primary tool used is the AWS Command Line Interface (CLI).

By j3rry Nov 25, 2025
BSidesNYC CTFd Writeup - Secret Map: Matroyshka?

BSidesNYC CTFd Writeup - Secret Map: Matroyshka?

It was the second part of "Secret Map: Scratching the surface" forensics challenge. The same map.jpg was provided.

By j3rry Nov 25, 2025
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