GlacierCTF 2026
- Starts
- Ends
- Runs for
- 24 hours
- Format
- Jeopardy (online)
- Rating weight
- 73.17 - Flagship
- Teams registered
- 6
Run by LosFuzzys, with prizes listed on CTFtime.
What the organisers say
We're excited to announce GlacierCTF 2026 for its fifth edition, a 24-hour jeopardy CTF organized by LosFuzzys. Join our discord at: https://discord.gg/DFYnRAME23 Infra sponsored by goo.gle/ctfsponsorship
Prep briefing
What past editions were made of
Counted across 38 challenges from 2025, 2024, 2023, 2022, 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”.
- misc 44%(11)
- web 40%(10)
- crypto 8%(2)
- pwn 8%(2)
What to have open when it starts
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 and esoteric languages
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 attacks and session tokens
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.
- CMakeListsunknown · 2023 · 4 writeups
- flag coin stage 1misc · 2022 · 2 writeups
- Flip Flip Hooray!unknown · 2025 · 2 writeups
- Skiliftunknown · 2023 · 2 writeups
- ArcticVaultmisc · 2024 · 1 writeup
- ARISAIunknown · 2023 · 1 writeup