Day 16: Power Cookie — picoCTF Web Exploitation Writeup

📰 Medium · Cybersecurity

Learn to exploit a web vulnerability by manipulating browser cookies in a picoCTF challenge

intermediate Published 20 Jun 2026

Action Steps

Launch a picoCTF instance for the Power Cookie challenge
Inspect the website's cookies using browser developer tools
Manipulate the cookie values to bypass security restrictions
Use the manipulated cookie to gain unauthorized access to the website
Analyze the website's code to understand the vulnerability and how to prevent it

Who Needs to Know This

Web developers and security teams can benefit from understanding how to identify and exploit vulnerabilities in web applications, particularly those related to browser cookies.

Key Insight

💡 Browser cookies can be manipulated to bypass security restrictions, highlighting the importance of proper cookie handling and validation in web applications.

Key Takeaways

Learn to exploit a web vulnerability by manipulating browser cookies in a picoCTF challenge

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Title: Day 16: Power Cookie — picoCTF Web Exploitation Writeup

URL Source: https://medium.com/@siyam.exe/day-16-power-cookie-picoctf-web-exploitation-writeup-6465342914a3?source=rss------cybersecurity-5

Published Time: 2026-06-20T13:01:02Z

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# Day 16: Power Cookie — picoCTF Web Exploitation Writeup | by Siyam | Jun, 2026 | Medium

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# Day 16: Power Cookie — picoCTF Web Exploitation Writeup

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A simple picoCTF web challenge where the website trusted a browser cookie a little too much.

Today marks the start of the web category.

We are starting with **Power Cookie** from picoCTF, or CyLab if we want to sound like we read the official branding properly.

Press enter or click to view image in full size

![Image 3](https://miro.medium.com/v2/resize:fit:700/1*1HVcKXuNDyc3QqH5xcKdnw.png)

The challenge did not give much explanation.

It simply asked me to launch an instance and visit the websi

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Day 16: Power Cookie — picoCTF Web Exploitation Writeup

Key Takeaways

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