KPMG CTF 2023
Tags: cybersecurity
Published: 2023-08-07 07:45:48

![A graph representing number of challenges that I solved](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/fzypp8a5913kxe61gd3i.png)
## **My First Capture The Flag Experience**

This is my very first Capture The Flag (CTF) experience. The CTF was organized by KPMG from 28th to 30th July 2023 and was specifically tailored for final year students pursuing a bachelor's degree in engineering. Having prior experience with CTFs through the learning modules in TryHackme, I was eagerly looking forward to participating in this CTF event.

## _Welcome Flag_

The first flag was the welcome flag, which happened to be the easiest one to find. All you had to do was go to the command line interface of the CTF website, run the 'ls' command to locate the 'flag.txt' file, and then use 'cat' to reveal the first flag, i.e., KPMG_CTF{W3lcom#_to_KICyb3rCTF}.

## _Cloud Pentest_

Next came the "Cloud Pentest" category. The description of the first flag in this category stated that my mission was to navigate the intricacies of AWS and retrieve confidential information within it. I was provided with a URL that pointed to an AWS S3 bucket. Upon opening the URL in my browser, a humorous gif titled "Try harder" appeared. In my quest for clues, I checked the resources shared by the CTF organizers. It was during this investigation that I discovered the AWS CLI tool and decided to explore further. After analyzing the URL, I realized it was an index.html file. Curious, I navigated to the main directory and found a text file named "flag-me-if-you-can," which led me to the second flag. The text file contained: KPMG_CTF{5247146a414c3ea2f7bec2c0f9b0664d}.


The next flag in this category also led to an AWS S3 bucket and required testing IAM policies. Initially, I attempted to brute force hidden directories using gobuster, but soon realized it was not a viable approach. Fortunately, I came across Network Chuck's YouTube video on AWS S3 and got introduced to the concept of bucket hunting. Thanks to the video, I acquired knowledge on using the AWS CLI tool to interact with buckets.

During my exploration, I discovered a JSON file containing the access key and secret key. I attempted to access other buckets associated with these credentials but was denied access. Despite several attempts, I couldn't make further progress, so I decided to move on to the next category.

## _Cryptography_

The next category was "Cryptography". Since I had no prior experience in cryptography, I referred to the documentation provided by the organizers to get an idea of it. I received a text file filled with gibberish and attempted to decrypt it using rumkin.com, but unfortunately, I wasn't successful despite multiple attempts.

While analyzing the cipher, I noticed that some pairs of alphabets repeated frequently, and this led me to believe they might represent common English words. Upon further investigation, I realized that the alphabets were reversed, indicating that the cipher was an atbash cipher. I decided to use boxentriq.com, where I pasted the cipher and obtained the decrypted version, which revealed the flag: KPMG_CTF{KPMGINDIACYBERTEAM}.

I decided to explore further and delve into different encoding methods. The subsequent challenge presented me with a text file and a description emphasizing words like "XORbit in the galaxy" and "XORs in the planet." It was apparent that this challenge involved XOR encoding.

To tackle it, I turned to a website called dcode.fr, which allowed me to brute force the cipher I had pasted using XOR decryption with different keys. After trying multiple keys, I finally managed to decrypt the cipher and reveal the flag: KPMG{Cryptic_art_unfolded}.

## _OSINT_

The next category was one of my favorites - OSINT (Open-Source Intelligence). In this challenge, I was given a person's name and asked to find out more about him. After a quick Google search, I discovered that he worked at KPMG. Intrigued, I visited his LinkedIn profile and carefully examined the information provided, hoping to find some clues.

As I scrolled through his profile, I clicked on "Show more" to expand the description, and there it was, hidden in plain sight - a cipher. To crack the cipher, I decided to test Google's Bard. I copied and pasted the cipher, and Google's Bard identified it as base64 encryption.

With this information, I headed to rumkin.com, where I selected base64 decryption and successfully retrieved the flag hidden within the cipher. The flag was revealed, and it read: KPMG_CTF{c2eb92b9f4666eb55512cabf4ac49d6e}.

The subsequent challenge required me to explore GitHub for answers and provided the name of a person. I conducted a search for that name on GitHub and came across a single repository. This repository had been recently created and contained two commits.

Upon examining the second commit, I discovered an HTML file that contained a link to an Instagram account. Curious about the connection, I followed the link to the Instagram account and stumbled upon a Google Maps review.

Despite thorough searching and investigation, I couldn't find any further hints or clues to progress in the challenge. Unfortunately, luck was not on my side this time, and the trail seemed to go cold.

## _Miscellaneous_

In the miscellaneous category, I was given a .pcap file to uncover the flag. Despite having experience working with the Wireshark tool, I couldn't decipher the direction I was meant to pursue. I tried relentlessly to analyze the .pcap file, but unfortunately, I hit a dead end.

After putting in considerable effort without making any significant progress, I eventually made the tough decision to give up on this particular challenge. Sometimes, challenges can be quite perplexing, and knowing when to take a step back and regroup is crucial in a Capture The Flag event.

## _Web Application Pentesting_

The next category was web application pentesting, and the first flag involved a URL leading to a login page. I attempted some basic SQL injections, but unfortunately, they did not yield the desired results.

## **Conclusion**

This was truly a remarkable experience for me. Initially, I registered only to gain insights into how a live CTF works, without any expectation of obtaining flags. However, as the event unfolded, I surprised myself by successfully capturing several flags. This accomplishment significantly boosted my confidence and ignited an even greater hunger to delve deeper into the realm of cybersecurity.

Participating in this CTF has reinforced my passion for learning and exploring new challenges in the cybersecurity domain. I eagerly anticipate engaging in more CTFs, as they present invaluable opportunities to enhance my skills, broaden my knowledge, and put my abilities to the test.

With each new challenge, I am committed to developing as a cybersecurity enthusiast, and I am excited about the thrilling journey that lies ahead. The experiences gained from these events will undoubtedly shape my growth and contribute to my journey of continuous improvement.

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