Welcome CTF 2025 Challenge List

Welcome

Done?	Name	Challenge Details	Estimated Difficulty (1-5)	Port Number
yes	Sanity Check	Sanity check	0	33000

pwn

Done?	Name	Challenge Details	Estimated Difficulty (1-5)	Port Number
yes	python challenge	simple pyjail unicode bypass	2	34508
yes	machine code repl	write x64 shellcode to read file	1	34568
yes	blast from the past	buffer overflow and ret2shellcode	2	35123
yes	echocrash	negative indexing in BSS to overwrite GOT entry	2.5	35124
yes	Rusty Vending Machine	Integer underflow in Rust	3	TBC
yes	sunshinefactory	overwrite least significant byte of a function pointer to call win function	4	33001

Web

Done?	Name	Challenge Details	Estimated Difficulty (1-5)	Port Number
yes	ski buddy	JWT token bruteforce, WebSocket hijacking	3	33335
yes	goliath	Go JSON footguns	2	3335
yes	vibecoder	JWT Verify Bypass	1	3334
yes	This is just one of those classic web challenges	Simple but hopefully non-trivial SQLite injection	2	33334
yes	This is just another one of those classic web challenges	SVG XXS	2	33333
yes	secure file storage	zip upload symlink	2	33336

Crypto

Done?	Name	Challenge Details	Estimated Difficulty (1-5)	Port Number
yes	cat and xor scam	skip-ahead attack on xorshift cipher	3	-
yes	eccentric cryptographic cipher	Exploit RSA fixed points to factorize modulus	2	-
yes	baby feistel	derive all of feistel with given state	1	32000
yes	what even is RSA	RSA with '2' as one of the primes	0	-
yes	please copy bthe ciphertext	simple XOR challenge	1	31410

RE

Done?	Name	Challenge Details	Estimated Difficulty (1-5)	Port Number
yes	mcshop	reverse a simple binary with extra steps to read flag file	1	34612
yes	flag checker	reverse a flag checker binary	1	-
yes	whats-in-the-bag	simple binary to re	1	-
yes	organised_person	custom packer to re	2	-
yes	wannaflag	self-extracting archive, re a binary + dll	3	-
yes	flag-checker-baby	reverse an (easier) flag checker binary	2	-

Forensics

Done?	Name	Challenge Details	Estimated Difficulty (1-5)	Port Number
yes	shy zipper	b64 decode after EOCD of zipfile	1	-
yes	scrambled_pawtrait	xor the 2 images	1	-
yes	stolen_disk	openssl encrypted disk partition	2.5	-
yes	memory_exercise	volatile memory analysis	1	-
yes	cosmic bit flip	png file alpha channel disabled via metadata	3	-
yes	solved hangman	file signature and file metadata to extend png file	2	-
yes	baby_wireshark	Wireshark filter http traffic	2	-
yes	shapes_galore	microsoft macros function	2	-

Misc

Done?	Name	Challenge Details	Estimated Difficulty (1-5)	Port Number
yes	the next beethoven	pwntools automation	1	34509
yes	crazy gifarfe	Polyglot file (GIFAR, GIF + JAR)	1	-
yes	ADS	alternate data streams, circular bit shifting and audio visualising using a spectrogram	1	-
yes	What The Church	Searching for LLM Benchmark, Using HuggingFace	2	-
yes	NUS Geographer	use NUSMods venues.json, regex, map scripting	4	-
yes	BTS	Python zip iterator argument order weirdness	2	-
yes	Insanity Check	Whitespace Language encoding in Sanity Check's service	2	-

OSINT

Done?	Name	Challenge Details	Estimated Difficulty (1-5)	Port Number
yes	Someone's salty	Retrieve pre-migration post on mastodon	1	-
yes	Party in the USA	geoguesser ahh for greyhats sticker in LA	1	-
yes	i love greyhats	internet archive	5	-

Blockchain

Done?	Name	Challenge Details	Estimated Difficulty (1-5)	Port Number

README Templates

Essentially, all README.md files should contain the following information

Things to include	Example
Challenge Details	Caesar thought of the perfect cipher. Can you break it?
Possible hints	Hint: What Caesar Cipher?
Key concepts	Scripting
Solution (Can also be a script)	Write a script to brute force all the combinations of the caesar cipher
Learning objectives	Learn about the Caesar Cipher
Flag	grey{salad_is_great_but_cipher_is_not}

Challenge folder format (challenges with services)

folder (your challenge name)
│   README.md
│   docker-compose.yml   
│
└───solve
│   │   (include all solution files here)
│
└───service
│   |   Dockerfile
│   |   (include all other files necessary for the service to run here e.g. .py files)
│      
└───distrib
    │   (include all files to be distributed to participants here)

Challenge folder format (challenges without services)

folder (your challenge name)
│   README.md
│
└───solve
│   │   (include all solution files here)
│      
└───distrib
    │   (include all files to be distributed to participants here)