Blocksec CTFs

A curated list of blockchain security Wargames, Challenges, and Capture the Flag (CTF) competitions and solution writeups.

Wargames and Writeups

• Ethernaut

  • Ethernaut CTF Solution by 0xIchigo
  • Ethernaut-CTF Solutions using Ape and Vyper by 0xJCN
  • Ethernaut CTF Series - All Things Security - Solutions in Solidity and Foundry by Aditya Dixit
  • Ethernaut Solutions by Aniket21mathur - Challenges 0-25
  • Ethernaut Solutions by cmichel - Challenges 0-21
  • Ethernaut Writeups by Macmod - Challenges 0-9
  • Ethernaut Solutions by tsauvajon - Challenges 1-11
  • Ethernaut Solutions by tinchoabbate
  • The Ethernaut CTF Writeup by Arseny Reutov - Challenges 0-6
  • Ethernaut Lvl 0 Walkthrough: ABIs, Web3, and how to abuse them by Nicole Zhu
  • Ethernaut Lvl 1 Walkthrough: how to abuse the Fallback function by Nicole Zhu
  • Ethernaut Lvl 2 Fallout Walkthrough: how simple developer errors become big mistakes by Nicole Zhu
  • Ethernaut Lvl 3 Coin Flip Walkthrough: how to abuse psuedo randomness in smart contracts by Nicole Zhu
  • Ethernaut Lvl 4 Telephone Walkthrough: how to abuse tx.origin & msg.sender by Nicole Zhu
  • Ethernaut Lvl 5 Token Walkthrough: How to abuse arithmetic underflows and overflows by Nicole Zhu
  • Ethernaut Lvl 6 Delegation Walkthrough: How to abuse the delicate delegatecall by Nicole Zhu
  • Ethernaut Lvl 7 Force Walkthrough — How to selfdestruct and create an Ether blackhole by Nicole Zhu
  • Ethernaut Lvl 8 Vault Walkthrough — How to read “private” variables in contract storage (with Truffle) by Nicole Zhu
  • Ethernaut Lvl 9 King Walkthrough: How bad contracts can abuse withdrawals by Nicole Zhu
  • Ethernaut Lvl 10 Re-entrancy Walkthrough: How to abuse execution ordering and reproduce the DAO hack by Nicole Zhu
  • Ethernaut Lvl 11 Elevator Walkthrough: How to abuse Solidity interfaces and function state modifiers by Nicole Zhu
  • Ethernaut Lvl 12 Privacy Walkthrough: How Ethereum optimizes storage to save space and be less gassy by Nicole Zhu
  • Ethernaut Lvl 13 Gatekeeper 1 Walkthrough: How to calculate smart contract gas consumption (and byte masking) by Nicole Zhu
  • Ethernaut Lvl 14 Gatekeeper 2 Walkthrough: How contracts initialize (and how to do bitwise operations) by Nicole Zhu
  • Ethernaut Lvl 15 Naught Coin Walkthrough: How to abuse ERC20 tokens and bad ICOs by Nicole Zhu
  • Ethernaut Lvl 16 Preservation Walkthrough: How to inject malicious contracts with delegatecall by Nicole Zhu
  • Ethernaut Lvl 17 Locked Walkthrough: How to properly use (and abuse) structs in Solidity by Nicole Zhu
  • Ethernaut Lvl 18 Recovery Walkthrough: How to retrieve lost contract addresses (in 2 ways) by Nicole Zhu
  • Ethernaut Lvl 19 MagicNumber Walkthrough: How to deploy contracts using raw assembly opcodes by Nicole Zhu
  • Ethernaut Challenges solutions by Asamartino - Challenges (0-21)
  • Ethernaut Challenges solutions by Simon - Challenges (0-21)
  • Ethernaut: Lvl 22 Dex - Writeups by thispost
  • Ethernaut: Lvl 23 Dex Two - Writeups by Naveen
  • Ethernaut: Lvl 24 Puzzle Wallet - Writeups by Lamby
  • Ethernaut: Lvl 25 Motorbike - Writeups by Lamby
  • Ethernaut: Lvl 26 DoubleEntryPoint - Writeups by D-Squared
  • Ethernaut Lvl 27 Good Samaritan Walkthrough: Custom Errors in Solidity by Chirag Agarwal
  • Ethernaut CTF Level 0 by D-Squared
  • Ethernaut CTF Level 1 by D-Squared
  • Ethernaut CTF Level 2 by D-Squared
  • Ethernaut CTF Level 3 by D-Squared
  • Ethernaut CTF Level 4 by D-Squared
  • Ethernaut CTF Level 5 by D-Squared
  • Ethernaut CTF Level 6 by D-Squared
  • Ethernaut Brownie Solutions by ptisserand
  • Ethernaut Truffle Solutions by tincho
  • Ethernaut Hardhat Solutions by MrToph
  • Ethernaut-x-Foundry Solutions by ciaranmcveigh5
  • Ethernaut CTF - Foundry Edition by StErMi
  • Ethernaut x Foundry - 0x0 Hello Ethernaut by 0xeval

• Damn Vulnerable DeFi

  • Damn Vulnerable DeFi - Foundry by alexbabits
  • Damn Vulnerable DeFi - Foundry edition by nicolasgarcia214
  • Damn Vulnerable DeFi - Foundry edition Challenge Solutions #1 to #12 on Medium.com by StErMi
  • DamnVulneraDeFi Solutions using Ape and Vyper by 0xJCN
  • DamnVulnerableDefi ABI smuggling challenge walkthrough (plus infographic) by ᴍatías Λereal Λeón
  • Damn Vulnerable DeFi Solutions by cmichel
  • Write-ups and lessons learned from Damn Vulnerable #DeFi by Damian Rusinek
  • Damn Vulnerable DeFi — Setup and Challenge #1 Walkthrough by iphelix
  • Damn Vulnerable DeFi — Challenge #2 Walkthrough by iphelix
  • Damn Vulnerable DeFi — Challenge #3 Walkthrough by iphelix
  • Damn Vulnerable DeFi — Challenge #4 Walkthrough by iphelix
  • Damn Vulnerable DeFi — Challenge #5 Walkthrough by iphelix
  • Damn Vulnerable DeFi — Challenge #6 Walkthrough by iphelix
  • Damn Vulnerable DeFi — Challenge #7 Walkthrough by iphelix
  • Damn Vulnerable DeFi — Challenge #8 Walkthrough by iphelix
  • Damn Vulnerable DeFi Video Solutions by Smart Contract Programmer
  • Damn Vulnerable DeFi v2 - part #1: Setup and Challenges 1 to 4 by patrickd
  • Damn Vulnerable DeFi V2 - #5 The Rewarder by patrickd
  • Damn Vulnerable DeFi V2 - #6 Selfie by patrickd
  • Damn Vulnerable DeFi V2 - #7 Compromised by patrickd
  • Damn Vulnerable DeFi V2 - #8 Puppet by patrickd
  • Damn Vulnerable DeFi V2 - #9 Puppet V2 by patrickd
  • Damn Vulnerable DeFi V2 - #10 Free Rider by patrickd
  • Damn Vulnerable DeFi V2 - #11 Backdoor by patrickd
  • Damn Vulnerable DeFi V2 - #12 Climber by patrickd
  • Damn Vulnerable DeFi V2 - #13 Junior Miners by patrickd
  • Damn Vulnerable DeFi V2 - #15 ABI Smuggling by Pranav Garg
  • Damn Vulnerable DeFi V3 Solutions by Blue Addler

• OnlyPwner

• Numen CTF 2023

  • Numen Cyber CTF Writeups
  • 2023 NUMEN CTF Writeup - GOATFinance by SunWeb3Sec
  • 2023 NUMEN CTF Writeup - Asslot, Counter, Exist, LenderPool, Wallet by SunWeb3Sec
  • 2023 NUMEN CTF Writeup - HEXP by SunWeb3Sec

• Security Challenges Factory for Starknet

• Boutiful

• MevSec CTF

• Mr Steal Yo Crypto

  • Mr Steal Yo Crypto Primer & Hints by 0xToshii
  • Mr Steal Yo Crypto Foundry by 0xToshii

• Capture the Ether

  • Capture the Ether Solutions by cmichel
  • Capture the Ether Solution by RD'
  • Capture the Ether Foundry Solutions by 0xraion

• EtherHack

  • EtherHack Contest Writeup

• Security Innovation Blockchain CTF

  • Security Innovation Blockchain CTF Solutions by Narendra Patel

• Cipher Shastra

  • Sherlock Writeup by Razzor

• DeFi Hack

  • DeFi Hack Hints & Hardhat Implementation by 0xToshii
  • DeFi Hack solutions: DiscoLP
  • DeFi Hack solutions: May The Force Be With You

• Gacha Lab

  • How Hackers Can Become “Lucky” in NFT Minting

• Curta CTF

  • Curta CTF Sudoku solution using Halmos by karma.
  • Puzzle #3 by Convergence Boy.

• Decently Safe DeFi

• MEV-Share CTF 2023

  • MEV-Share CTF Writeups by minaminao

• Only Pwner

• Web3Pwn

Challenges and Writeups

• SmartSecRiddles by marjon-call

• [Project SEKAI CTF 2023]

  • Project SEKAI CTF 2023 Re-Remix Writeup by minaminao.

• Whitenoise CTF

  • Doves in the wind solution by Oren Yomtov.

• Code is Law 1 by Oren Yomtov.

• Code is Law 2 by Oren Yomtov.

• Dragonfly CTF

  • Dragonfly CTF Solutions
  • PuzzleBox CTF by smitrajput

• Trust Chain CTF

• Huff Puzzles by RareSkills.

• EKO2022 Enter the metaverse CTF

  • EKO2022 Enter the metaverse CTF Challenge 1 — Phoenixtto by StErMi
  • EKO2022 Enter the metaverse CTF Challenge 2 — Metaverse Supermarket by StErMi.

• HappyNewYearCTF by Convergence Boy

  • Making of HappyNewYear CTF Puzzle by Convergence Boy

• Bountiful: Fe Challenge

  • Solution by Plotchy.

• I Am The Optimizer

  • Solution by Riley Holterhus.
  • Solution by NoahCitron.

• BalsnCTF

  • BalsnCTF 2022 Smart Contract Challenges Writeup

• CTF Lending by MrToph

• EthernautDAO Challenges

  • EthernautDAO Solutions using Ape and Vyper by 0xJCN
  • List of all challenges and solutions
  • List of challenges with solutions and writeups from beskay
  • CTF Level 1: PrivateData - Writeup by Giovannidisiena.eth
  • CTF Level 2: Wallet - Writeup by StErMi
  • CTF Level 3: Car Market - Writeup by StErMi
  • CTF Level 4: Vending Machine - Writeup by StErMi
  • CTF Level 6: Hackable Contract - Writeup by StErMi
  • CTF Level 8: VNFT - Writeup by beskay
  • CTF Level 9: EtherWallet - Writeup by beskay
  • CTF Level 10: Vault - Writeup by beskay
  • CTF Level 11: Staking - Writeup by beskay

• SecDim

  • Play - AppSec Games and Challenges
  • Learn - Git based labs on real world exploits

• Secureum-A-MAZE-X

  • A-MAZE-X CTF Walkthrough | Part I by Matias
  • A-MAZE-X CTF Walkthrough | Part II by Matias
  • A-MAZE-X CTF Walkthrough | Part III by Matias
  • A-MAZE-X CTF Walkthrough | Part IV by Matias

• Secureum A-MAZE-X Stanford

  • Secureum A-MAZE-X Stanford CTF by patrickd

• Secureum Bootcamp

  • RACE #13 Of The Secureum Bootcamp Epoch∞ by patrickd
  • RACE #14 Of The Secureum Bootcamp Epoch∞ by patrickd

• Sol Challenges and Solutions

• Hats Finance Challenge

  • Solution
  • Solution

• Hackxyk Stablecoin Challenge

  • Solution by Abhishek Vispute
  • Solution by Arbaz Hussain

• Immunefi Community Challenges by Immunefi

• EVM puzzles by fvictorio

  • Learning Ethereum Virtual Machine Opcodes With EVM Puzzles by patrickd
  • EVM Puzzles – Second Wind by patrickd
  • Let’s play EVM Puzzles — learning Ethereum EVM while playing!
  • Solving more-evm-puzzles differently? | Part I by Matias
  • Solving more-evm-puzzles differently? | Part II by Matias
  • Yet another evm puzzle by Matias
  • Write-ups for yet another EVM puzzle1 by 0xNorman
  • Write-up for yet another EVM puzzle2 by 0xNorman
  • Write-up for yet another EVM puzzle3 by 0xNorman
  • Write-up for yet EVM puzzle4 by 0xNorman
  • Write-up for yet another EVM puzzle5 by 0xNorman

• More EVM puzzles

  • Solutions - Part 1 by patrickd
  • Solutions - Part 2 by patrickd

• Solana Security Workshop by Neodyme

  • Solution by Christoph Michel

• Interview Contracts by Halborn

• Pinball Challenge by samczsun

  • Solution by KarmaComa
  • Solution by adietrichs
  • Solution by Kane Wallmann

• NCCGroup GOAT Casino

• Damn Vulnerable Crypto Wallet

• Cryptohunt by p4d

• Impossible by u/eththrowaway4

• Break My Contract, Steal My Money Challenges

  • Break My Contract, Steal My Money - A Solidity Riddle
  • Break My Contract (Part 1) - Buffer Overflow Solution
  • Break My Contract, Steal My Money - A Solidity Riddle (Part 2)

• Hacking smart contracts for fun and profit by István András Seres

• Vyperpunk

• Challenges by @robot_dreams

• Underhanded Solidity Contest

  • Submissions for Underhanded Solidity Contest 2022
  • Submissions for Underhanded Solidity Contest 2020

• Solidity Riddles by RareSkills

CTFs and Writeups

• GPN CTF 2023

  • GPN CTF 2023 writeup by Kaiziron

• SEETF

  • SEETF 2023 Writeup by minaminao
  • SEETF 2023 writeup by Kaiziron
  • SEETF 2022 Write List

• LA CTF 2023

  • LA CTF 2023 Writeup by Kaiziron

• N1CTF 2022

  • N1CTF 2022 Solana Challenges Writeups

• Paradigm CTF 2022 - 2022

  • Community Solutions:
    • Paradigm CTF 2022 Write-up by The Duck (Theori)
    • Statemind's solutions(11 solved)
    • Paradigm CTF 2022 Writeup by Inspex
    • minaminao solutions
    • Kaiziron solutions
    • Paradigm CTF 2022: Write-Up Collection
    • Paradigm CTF 2022 - Electric Sheep by patrickd
    • Paradigm CTF 2022 - Trapdooor & Trapdoooor by patrickd
    • 0xMonaco writeup by brock
    • 0xMonaco #1 place writeup by Oage
    • 0xMonaco writeup by Abdulla
    • 0xMonaco exploit by Brock Elmore
    • Unlocking the Lockbox2 by Soham Zemse
    • Vanity by Daniel Von Fange
    • Merkledrop and Vanity by iFrostizz
    • PARADIGM CTF 2022 Question Analysis 1 — RESUCE by Numen Cyber Labs
    • PARADIGM CTF 2022 Question Analysis 2 — Source Code Analysis by Numen Cyber Labs
    • PARADIGM CTF 2022 Question Analysis 3 - Lockbox2 Analysis by Numen Cyber Labs
    • PARADIGM CTF 2022 Question Analysis 4 -MerkleDrop by Numen Cyber Labs
    • Electric Sheep - Stealing gas tokens from the GSN-enabled MultiSig by Decurity

• Sherlock CTF

• Solutions

• The Standoff Digital Art Competition

  • Разбор заданий конкурса на взлом NFT “The Standoff Digital Art”

• Paradigm CTF - 2021

  • Official Challenges and Solutions:
    • paradigm-ctf-2021
  • Community Solutions:
    • Paradigm CTF 2021 Solutions and Github repo by cmichel
    • BabyRev and Upgrade Solutions by Ansgar Dietrichs
    • [Paradigm JOP Solution on Twitch Part 1 and Part 2 by Ansgar Dietrichs
    • Paradigm CTF 2021 Solutions by thegostep
    • BabyCrypto, BabySandbox, and Lockbox writeups by roynalnaruto
    • BabyCrypto Challenge by Team Dilicious (Sam Wilson)
    • Broker Challenge by Team Dilicious (Sam Wilson)
    • BabyRev Challenge by Team Dilicious (Sam Wilson)
    • Bank Challenge by Team Dilicious (smarx)
    • Vault Challenge by Team Dilicious (smarx)
    • Paradigm CTF Solutions by Furucombo
    • Swap Challenge by samczsun
    • Solutions by patrickd

• 0xPOLAND - 2020

  • 0xPOLAND — Adventure Awaits by iphelix

• AnChain CTF - 2020

  • DeFi Detectives: Chef Nomi Investigation Notes by iphelix
  • DeFi Detectives: Discovering the Secrets of the DeFi Ecosystem
  • Congratulations Bitcoin Bounty Hunters! The World’s First Blockchain Investigation Contest.

• Sharky CTF - 2020

  • Sharky CTF: Blockchain Level 0 to 4 Writeup by Nithilan Pugal
  • Sharky CTF Blockchain Challenges by Imagin

• CipherShastra CTF

  • Sherlock
  • Minion
  • Limitless
  • Shilpkaar
  • UnDeAD
  • ThirtyFive
  • Maya
  • Gambler

• Donjon CTF - 2020

  • CTF 2020: Capture the Fortress
  • Ledger Donjon CTF: Rationale and Winners!

• Chain Heist - 2019

  • Chain Heist and blockchain security at DEF CON 2019
  • Chain Heist CTF Writeup by iphelix

• Capture the Coin - 2019

  • “Capture the Coin” at Defcon and you could win big
  • How the Coinbase Security team deployed CTFd to Power our First Capture the Flag contest at Defcon 27
  • Congratulations Capture the Coin participants!
  • Capture the Coin — Trivia Solutions
  • Capture the Coin — Blockchain Category Solutions
  • Capture the Coin — Cryptography Category Solutions
  • Capture the Coin CTF write-up by Arpox

• ConsenSys Dilligence Ethereum Hacking Challenge - 2018

  • Consensys CTF Writeup by samczsun

• Code Blue PolySwarm Challenge - 2018

  • PolySwarm Smart Contract Hacking Challenge Writeup by Arseny Reutov

• Real World CTF (Acoraida Monica Challenge) - 2018

  • Challenge files and Solution by LiveOverflow
  • Ethereum Smart Contract Code Review #1 - Real World CTF 2018 by LiveOverflow
  • Jump Oriented Programming: Ethereum Smart Contract #2 - Real World CTF 2018 by LiveOverflow
  • Ethereum Smart Contract Backdoored Using Malicious Constructor by LiveOverflow

• Authio Solidity CTF

  • Challenges:
    • Part 1 - Function Types
    • Part 2 - Safe Execution
    • Part 3 - HoneyPot
    • Part 4 - Read the Fine Print
    • Part 5 - Mirror Madness
  • Solidity CTF - Part 1: "Function Types
  • Solidity CTF — Part 2: “Safe Execution”by Alexander Wade
  • Solidity CTF — Part 3: “HoneyPot” by Alexander Wade
  • Solidity CTF — Part 4: Read the Fine Print by Alex Towle
  • Solidity CTF - Part 5: Mirror Madness by Paul Vienhage

• ZeroNights ICO Hacking Contest - 2017

  • ZeroNights ICO Hacking Contest Writeup by Arseny Reutov

• QuillCTF

  • Road Closed
  • Confidential Hash
  • VIP Bank
  • safeNFT
  • D31eg4t3
  • Collatz Puzzle
  • True XOR
  • Pelusa
  • WETH 10
  • Gate
  • Panda Token