PwnSec CTF 2026
- Starts
- Ends
- Runs for
- 24 hours
- Format
- Jeopardy (online)
- Rating weight
- 33.89 - Strong field
- Teams registered
- 124
Run by PwnSec, with prizes listed on CTFtime.
What the organisers say
PwnSec is proud to present its 3rd edition CTF. Tune in for top jeopardy madness built by our team featuring web, crypto, reverse engineering, binary exploitation, cloud, forensics, misc, mobile, and more!
Prep briefing
What past editions were made of
Counted across 21 challenges from 2025, 2024, using the categories the scoreboards themselves used. Two things to hold in mind while reading it. The archive indexes challenges that someone published a solution to, not whole scoreboards, so this is the shape of what people wrote about rather than of everything that was set. And where a scoreboard gave no category the challenge lands in misc, so a large misc slice means “unlabelled” rather than “miscellaneous”.
- crypto 43%(6)
- web 36%(5)
- misc 14%(2)
- pwn 7%(1)
What to have open when it starts
Crypto
Have the cipher identifier open on the first paste. Most of the round-one crypto is a classical cipher or an RSA parameter mistake, and both are recognised faster than they are solved.
- Cipher identifier and automatic decoder
- RSA decryption and attack runner
- XOR cipher decoder and key recovery
- Vigenere cipher solver with automatic key recovery
- Modular arithmetic and number theory toolkit
New to this? Read Classical ciphers and frequency analysis, XOR and the cost of reusing a key, Block ciphers, modes and oracles, RSA and the parameters that break it, Discrete logs, Diffie-Hellman and elliptic curves
Web
Read the token before you read the source. A session cookie that decodes is the shortest path through half the web board.
- JWT decoder and signature verifier
- Flask session cookie decoder
- HTTP request replayer
- Directory and path scanner
- HTTP security header analyzer
New to this? Read Web recon and attack surface, Injection: SQL and everything after it, Client-side: XSS and the browser's trust model, Sessions, tokens and access control, Server-side takeover: from input to execution, APIs, GraphQL and application logic
Misc
Misc is whatever did not fit, which in practice means encodings and esolangs. Identify, do not guess.
- Cipher identifier and automatic decoder
- Recipe builder: chain decodes and transforms
- Brainfuck and esolang decoder
- Base64 decoder and encoder
- Regex tester with match offsets and capture groups
New to this? Read Recognising encodings, Misc, esolangs and prompt injection
The challenges people wrote about most
From previous editions, ordered by how many published solutions each attracted. Reading two solutions to one of these is the closest thing to a warm-up for this event that exists.