Writeup For RED

by ADMIN 16 views

Introduction

PicoCTF 2025 is an annual cybersecurity competition organized by Carnegie Mellon University's Computer Emergency Response Team (CERT). The event aims to provide a platform for students and professionals to develop their skills in various areas of cybersecurity, including web exploitation, binary exploitation, and cryptography. In this writeup, we will focus on the challenges faced by the RED team, providing a comprehensive overview of the obstacles and solutions encountered during the competition.

Challenge 1: Web Exploitation - "Easy Web"

The first challenge, "Easy Web," was a basic web exploitation challenge that required participants to identify and exploit a SQL injection vulnerability in a web application. The challenge was designed to introduce participants to the basics of web exploitation and provide a foundation for more complex challenges later in the competition.

Challenge Description

The challenge presented a simple web application with a login form that accepted user input. The application was vulnerable to SQL injection attacks, allowing participants to inject malicious SQL code and extract sensitive information from the database.

Solution

To solve this challenge, participants needed to identify the SQL injection vulnerability and craft a malicious SQL query to extract the flag. The solution involved using a tool like Burp Suite to intercept and modify the HTTP requests sent to the web application. By analyzing the application's source code, participants could identify the vulnerable parameter and craft a SQL injection attack to extract the flag.

Challenge 2: Binary Exploitation - "Easy Binary"

The second challenge, "Easy Binary," was a basic binary exploitation challenge that required participants to identify and exploit a buffer overflow vulnerability in a binary executable. The challenge was designed to introduce participants to the basics of binary exploitation and provide a foundation for more complex challenges later in the competition.

Challenge Description

The challenge presented a simple binary executable that accepted user input and performed a series of operations. The binary was vulnerable to buffer overflow attacks, allowing participants to inject malicious code and execute arbitrary system calls.

Solution

To solve this challenge, participants needed to identify the buffer overflow vulnerability and craft a malicious payload to inject into the binary. The solution involved using a tool like GDB to analyze the binary's memory layout and identify the vulnerable function. By crafting a malicious payload that exploited the buffer overflow vulnerability, participants could execute arbitrary system calls and extract the flag.

Challenge 3: Cryptography - "Easy Crypto"

The third challenge, "Easy Crypto," was a basic cryptography challenge that required participants to identify and exploit a weakness in a cryptographic algorithm. The challenge was designed to introduce participants to the basics of cryptography and provide a foundation for more complex challenges later in the competition.

Challenge Description

The challenge presented a simple cryptographic algorithm that accepted user input and performed a series of operations. The algorithm was vulnerable to a specific attack, allowing participants to extract the flag.

Solution

To solve this challenge, participants needed to identify the weakness in the cryptographic algorithm and craft a malicious input to exploit the vulnerability. The solution involved using a tool like OpenSSL to analyze the algorithm's implementation and identify the weakness. By crafting a malicious input that exploited the weakness, participants could extract the flag.

Challenge 4: Web Exploitation - "Medium Web"

The fourth challenge, "Medium Web," was a more complex web exploitation challenge that required participants to identify and exploit a vulnerability in a web application. The challenge was designed to provide a more challenging experience for participants and require them to apply their knowledge of web exploitation techniques.

Challenge Description

The challenge presented a more complex web application with multiple vulnerabilities, including a SQL injection vulnerability and a cross-site scripting (XSS) vulnerability. Participants needed to identify and exploit both vulnerabilities to extract the flag.

Solution

To solve this challenge, participants needed to identify both vulnerabilities and craft malicious SQL queries and JavaScript code to exploit them. The solution involved using a tool like Burp Suite to intercept and modify the HTTP requests sent to the web application. By analyzing the application's source code, participants could identify the vulnerable parameters and craft malicious SQL queries and JavaScript code to extract the flag.

Challenge 5: Binary Exploitation - "Medium Binary"

The fifth challenge, "Medium Binary," was a more complex binary exploitation challenge that required participants to identify and exploit a vulnerability in a binary executable. The challenge was designed to provide a more challenging experience for participants and require them to apply their knowledge of binary exploitation techniques.

Challenge Description

The challenge presented a more complex binary executable with multiple vulnerabilities, including a buffer overflow vulnerability and a format string vulnerability. Participants needed to identify and exploit both vulnerabilities to extract the flag.

Solution

To solve this challenge, participants needed to identify both vulnerabilities and craft malicious payloads to inject into the binary. The solution involved using a tool like GDB to analyze the binary's memory layout and identify the vulnerable functions. By crafting malicious payloads that exploited the buffer overflow and format string vulnerabilities, participants could execute arbitrary system calls and extract the flag.

Challenge 6: Cryptography - "Medium Crypto"

The sixth challenge, "Medium Crypto," was a more complex cryptography challenge that required participants to identify and exploit a weakness in a cryptographic algorithm. The challenge was designed to provide a more challenging experience for participants and require them to apply their knowledge of cryptography techniques.

Challenge Description

The challenge presented a more complex cryptographic algorithm with multiple vulnerabilities, including a weakness in the encryption algorithm and a weakness in the key exchange protocol. Participants needed to identify and exploit both weaknesses to extract the flag.

Solution

To solve this challenge, participants needed to identify both weaknesses and craft malicious inputs to exploit the vulnerabilities. The solution involved using a tool like OpenSSL to analyze the algorithm's implementation and identify the weaknesses. By crafting malicious inputs that exploited the weaknesses, participants could extract the flag.

Conclusion

PicoCTF 2025 was a challenging competition that required participants to apply their knowledge of web exploitation, binary exploitation, and cryptography techniques. The challenges presented a range of obstacles, from basic to complex, and required participants to think creatively and apply their skills in a practical setting. This writeup provides a comprehensive overview of the challenges faced by the RED team and highlights the key techniques and strategies used to solve each challenge.

Introduction

PicoCTF 2025 was a challenging competition that required participants to apply their knowledge of web exploitation, binary exploitation, and cryptography techniques. In this Q&A guide, we will provide answers to some of the most frequently asked questions about the competition, including the challenges, the format, and the rules.

Q: What is PicoCTF 2025?

A: PicoCTF 2025 is an annual cybersecurity competition organized by Carnegie Mellon University's Computer Emergency Response Team (CERT). The event aims to provide a platform for students and professionals to develop their skills in various areas of cybersecurity.

Q: What are the challenges in PicoCTF 2025?

A: The challenges in PicoCTF 2025 include web exploitation, binary exploitation, and cryptography challenges. The challenges are designed to test participants' skills in identifying and exploiting vulnerabilities in web applications, binary executables, and cryptographic algorithms.

Q: What is the format of the competition?

A: The competition is divided into two phases: the qualification phase and the final phase. In the qualification phase, participants are required to solve a series of challenges to earn points. The top participants with the highest points are then selected to participate in the final phase, where they are required to solve a series of more complex challenges.

Q: What are the rules of the competition?

A: The rules of the competition include:

  • Participants must register for the competition before the deadline.
  • Participants must agree to the terms and conditions of the competition.
  • Participants must not use any unauthorized tools or resources to solve the challenges.
  • Participants must not disclose any information about the challenges or the competition to anyone.

Q: How do I register for the competition?

A: To register for the competition, participants must visit the official website of PicoCTF 2025 and fill out the registration form. Participants must provide their name, email address, and other required information.

Q: What are the prizes for the competition?

A: The prizes for the competition include:

  • The top three participants will receive a cash prize of $10,000, $5,000, and $2,000, respectively.
  • The top three participants will also receive a trophy and a certificate of achievement.
  • The top participants will also receive a chance to participate in a special workshop or training program.

Q: How do I prepare for the competition?

A: To prepare for the competition, participants should:

  • Familiarize themselves with the challenges and the format of the competition.
  • Practice solving web exploitation, binary exploitation, and cryptography challenges.
  • Join online communities and forums to learn from other participants and get tips and advice.
  • Stay up-to-date with the latest developments in cybersecurity and the competition.

Q: What are the most common mistakes made by participants?

A: The most common mistakes made by participants include:

  • Not reading the challenge description carefully.
  • Not using the correct tools or resources.
  • Not testing their solutions thoroughly.
  • Not submitting their solutions on time.

Q: How do I stay motivated during the competition?

A: To stay motivated during the competition, participants should:

  • Set realistic goals and deadlines for themselves.
  • Break down the challenges into smaller, manageable tasks.
  • Celebrate their successes and learn from their failures.
  • Stay focused and avoid distractions.

Conclusion

PicoCTF 2025 was a challenging competition that required participants to apply their knowledge of web exploitation, binary exploitation, and cryptography techniques. This Q&A guide provides answers to some of the most frequently asked questions about the competition, including the challenges, the format, and the rules. By following the tips and advice provided in this guide, participants can prepare themselves for the competition and stay motivated during the event.