CryptoMedium

Weak RSA Implementation

rsacryptographyfactorization

UNG Cybersecurity Faculty

1/15/2025

250 points

Challenge Files

Challenge Instructions

README.txt

💡 Tip: Additional challenge-specific files are located in the assets folder. Check the instructions file for details.

Challenge Overview

A certificate authority was compromised using weak RSA keys. The attacker used small prime numbers making factorization possible. Factor the provided public key to decrypt the message and recover the flag.

Learning Objectives

Apply crypto analysis techniques
Use professional security tools
Understand real-world attack scenarios
Document findings professionally

Tools You May Need

Python with sympy or gmpy2
factordb.com for factorization
OpenSSL for key operations

Getting Started

Review the challenge description carefully
Gather and examine all provided materials
Apply systematic analysis methodology
Document your findings as you progress
Submit the flag when discovered

Flag Format

All flags follow the format: ung{descriptive_text}

Good luck!

Hints

💡 Hint 1 (Click to reveal)

Start by examining the basic artifacts and evidence provided

💡 Hint 2 (Click to reveal)

Use industry-standard tools for this type of analysis

💡 Hint 3 (Click to reveal)

The flag follows the format ung{...} with descriptive text