SekaiCTF 2024 Writeup

CTFTime event link: https://ctftime.org/event/2243

Writeup

• Web
  1. Tagless
  2. Intruder

Background

• Starts: 17 Aug. 2024, 00:00 UTC
• Ends: 19 Aug. 2024, 00:00 UTC

SekaiCTF is back for its third iteration! This year’s competition will feature various categories designed to test participants’ skills and incentivize learning. Our CTF will have more difficult challenges, and are catered towards intermediate and advanced players—however, there will still be beginner-friendly challenges to welcome players on the newer side.

Categories:

• Miscellaneous
• Cryptography
• Reverse Engineering
• Pwn
• Programming (PPC)
• Web
• Blockchain

Overview

• Team: ARESx
• Team Solves: 5/34
• Individual Solves: 3/34
• Score: 378
• Global Rank: 135/1230
• Overall Difficulty To Me: ★★★★★★★★☆☆

What I’ve learned in this CTF

• Web
  1. Tagless - Reflected XSS and CSP bypass
  2. Intruder - ASP.NET Core dynamic LINQ injection to RCE (CVE-2023-32571)