CTF write-ups written by me. Mostly crypto and blockchain!
- DiceCTF 2023
- Crypto 199 - BBBB - Writeup
- LCG parameter selection to make RNG cyclic + Coppersmith Attack
- Crypto 199 - BBBB - Writeup
- CODEGATE 2022 Final
- Blockchain 500 - Look It Up - Writeup-EN, Writeup-KR
- Plonkup + frozen heart vulnerability + Solidity Optimizer Keccak Caching Bug
- Blockchain 500 - Look It Up - Writeup-EN, Writeup-KR
- RCTF 2022
- LakeCTF 2022
- angstromCTF 2022
- Crypto 110 - logloglog - Writeup
- Pohlig Hellman Algorithm for groups of prime-power order.
- Crypto 110 - logloglog - Writeup
- Plaid CTF 2022
- Crypto 400 - choreography - Writeup
- Complementation Slide + Twisted Slide Attack on generalized Feistel Structure.
- Crypto 400 - choreography - Writeup
- LINE CTF 2022
- Crypto 138 - Baby crypto revisited - Writeup
- Reduction to ECDSA biased nonce atack.
- Crypto 138 - Baby crypto revisited - Writeup
- zer0pts CTF 2022
- Crypto 304 - Karen - Writeup
- Solving Hidden Subset Sum Problem with Nguyen-Stern algorithm.
- Crypto 304 - Karen - Writeup
- POC Cutting Edge CTF 2021
- Crypto 994 - vpoly - Writeup
- Solving discrete logarithm problem over finite field.
- Crypto 994 - vpoly - Writeup
- InCTF 2021
- KAPO 2020
- Crypto CTF 2020
- Crypto 316 - Fatima - Writeup
- Solve tiny ECDLP and write inverse functions.
- Crypto 285 - Complex to Hell - Writeup
- Brute key matrix using flag oracle.
- Crypto 142 - One Line Crypto - Writeup
- Weak prime generation logic for textbook RSA.
- Crypto 95 - Gambler - Writeup
- Solve cubic equation over polynomial ring.
- Crypto 90 - Three Ravens - Writeup
- Small message with single factor leak.
- Crypto 55 - Amsterdam - Writeup
- Binomial coefficient based encoding.
- Crypto 29 - Trailing Bits - Writeup
- Trucated plaintext.
- Crypto 316 - Fatima - Writeup
- Defenit CTF 2020
- Pwn2Win CTF 2020
- DEF CON CTF Qualifier 2020
- PlaidCTF 2020
- TAMUctf 2020
- Crypto 338 - ETERNAL_GAME - Writeup
- Hash length extension attack.
- Web 262 - MENTALMATH - Writeup
- Ajax code injection.
- Web 122 - FILESTORAGE - Writeup
- LFI + php session poisoning.
- Web 50 - PASSWORD_EXTRACTION - Writeup
- Blind SQL injection.
- Misc 50 - INSTAGRAM - Writeup
- JPEG marker recovery.
- Misc 50 - BLIND - Writeup
- Reverse shell.
- Crypto 338 - ETERNAL_GAME - Writeup
- zer0pts CTF 2020
- Pragyan CTF 2020
- Crypto 150 - AskTheOracle - Writeup
- Oracle Padding Attack.
- Crypto 150 - AskTheOracle - Writeup
- nullcon HackIM 2020
- Crypto 419 - SecureLinearFunctionEvaluation - Writeup
- Break Bellare-Micali OT by simple math.
- Crypto 419 - SecureLinearFunctionEvaluation - Writeup
- WhiteHat Grand Pix 06 Quals
- Crypto 200 - Cryptography 01 - Writeup
- Simple substitution cipher.
- Crypto 200 - Cryptography 01 - Writeup
- Christmas CTF 2019
- HITCON CTF 2019 Quals
- KAPO 2019
- CSAW CTF Qualification Round 2019
- Affinity CTF 2019 Quals
- HackCon 2019
- Crypto 467 - AgainAndAgainAndAgain - Writeup
- Multiple encryption with Rabin cryptosystem.
- Crypto 467 - AgainAndAgainAndAgain - Writeup
- Crypto CTF 2019
- ISITDTU CTF 2019 Quals
- Crypto 304 - Chaos - Writeup
- Simple substitution cipher.
- Crypto 100 - Easy RSA 1 - Writeup
n
ande
have similar size, so apply Boneh-Durfee attack.
- Crypto 919 - Easy RSA 2 - Writeup
- Crack multiprime RSA with Fermat factorization.
- Crypto 238 - Old Story - Writeup
- Base64 encoding with guessing.
- Crypto 395 - decrypt to me - Writeup
- Weak prng.
- Crypto 304 - Chaos - Writeup
- Facebook CTF 2019
- DEF CON CTF Qualifier 2019
- Crypto 182 - tania - Writeup
- DSA with LCG nonces are broken using LLL, or apply biased nonce attack.
- Crypto 182 - tania - Writeup
- Harekaze CTF 2019