picoCTF - WebDecode

Posted on Jan 25, 2026
  • URL: https://play.picoctf.org/practice/challenge/427
  • Title: WebDecode
  • Tags: Easy, Web Exploitation, picoCTF 2024, browser_webshell_solvable
  • Author: Nana Ama Atombo-Sackey
  • Started: 9 July 2025
  • Solved: 9 July 2025
  • Description: Do you know how to use the web inspector? Additional details will be available after launching your challenge instance.

The website appeared to be trolling 😬

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According to the description, I was expected to inspect the web using devtools. There were 3 files, index.html, about.html, contact.html

After inspecting about.html, it shows a message and a section element with a strange attibute value.

alt text

cGljb0NURnt3ZWJfc3VjYzNzc2Z1bGx5X2QzYzBkZWRfMTBmOTM3NmZ9

Usually for these challenges, the flag is encrypted using base64

`alt text

picoCTF{web_succ3ssfully_d3c0ded_10f9376f}