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billh
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billh
@hibillh
blockchain security prev @ambergroup_io @stakefish | Opinions are my own
Taiwan
Joined March 2018
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  • user avatar
    billh
    @hibillh
    Oct 30, 2023
    This year I solved 10 challenges @paradigm_ctf Regrettably, due to insufficient knowledge in cryptography, I couldn't crack two cryptography challs. Despite intense competition and not making it into the top ten, it was still a really fun experience. Onwards to more learning!
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    16K016K
  • user avatar
    billh
    @hibillh
    Mar 18, 2024
    Thrilled to win the @OpenZeppelin CTF! The XYZ challenge was my favorite, a meticulously designed puzzle based on a CDP (Collateralized Debt Position) protocol. It showcased that not all accounting tokens are created equal in a protocol, and how a simple rounding decision can
    user avatar
    OpenZeppelin
    @OpenZeppelin
    Mar 18, 2024
    Ethernaut CTF 2024 has wrapped up! 🥇 @ambergroup_io 🥈 @DecurityHQ 🥉 @statemindio Stay tuned for rewards and POAPs via email this week👀 Until next time! Check out challenges & solutions here: github.com/OpenZeppelin/c…
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    6.2K06.2K
  • user avatar
    billh
    @hibillh
    Mar 24, 2024
    We are now in phase 2! Here is my writeup for the @curta_ctf challenge 'NumberHeist', devised by @0xOwenThurm. Any feedback is welcome.
    Curta NumberHeist Writeup - HackMD
    Curta NumberHeist Writeup - HackMD
    From hackmd.io
    6K06K
  • user avatar
    billh
    @hibillh
    Dec 4, 2023
    I'm grateful that we were able to take 3rd place in the #BlazCTF competition. Kudos to my team @chiachih_wu @ashleyhsu_eth @neeksec for their amazing work. Hats off to the organizers @hackthedefi for their thoughtfully crafted challenges, providing an opportunity for
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    𝕗𝕦𝕫𝕫𝕝𝕒𝕟𝕕
    @fuzzland_
    Dec 4, 2023
    Blaz CTF 2023 has concluded 🥳🥳. Congrats to @Offside_Labs @ChainLight_io and Amber Labs for securing the Top 3, and kudos to everyone who participated.
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    9.2K09.2K
  • user avatar
    billh
    @hibillh
    Aug 22, 2022
    We ranked 6th out of more than 400 teams! Target top five next year🫡 Thanks for the awesome challenges @paradigm_ctf
    user avatar
    Paradigm CTF
    @paradigm_ctf
    Aug 22, 2022
    We're done! Thanks to everyone for playing Paradigm CTF 2022. Congrats to @theori_io, @hexens, and @PwningEth for scoring in the top 3! A big shoutout to @0xGreg_, @Mauricio_0218, @zellic_io, @osec_io, and @dumbcontract2 for guest authoring challenges. See you next year!
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  • user avatar
    billh
    @hibillh
    Jul 3, 2023
    Fun fact: the value of signatureClaimed is never checked in the contract.
    user avatar
    Daniel Von Fange
    @danielvf
    Jul 3, 2023
    The AzukiDAO, formed to sue Azuki, has had their governance token hacked in a classic signature malleability attack. Remember, an attacker can take a valid, signed signature, and make another, different valid signature over the same data. Sigs are not unique identifiers! 1/3
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    11K011K
  • user avatar
    billh
    @hibillh
    Nov 18, 2023
    Just earned my first First Blood on @curta_ctf by solving Stake Frens!
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    1.8K01.8K
  • user avatar
    billh
    @hibillh
    Feb 27, 2023
    Participated in race-15 at @TheSecureum. Happy to be on the top 32 leaderboard on my second try.
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    1.4K01.4K
  • user avatar
    billh
    @hibillh
    Oct 6, 2021
    🚨🚨🚨Rug Alert: The emergency admin in @GeistFinance contracts is an EOA, and it gives them the ability to pause the contract and upgrade their proxy after timelock delay. ftmscan.com/tx/0x7cdd4bc38…
  • user avatar
    billh
    @hibillh
    Oct 21, 2023
    I devised the challenge SoulBound for the @Quill_Academy CTF and warmly invite everyone to partake in this event while enjoying the process.👨‍💻
    user avatar
    DevsOnChain 🥷⛓️
    @DevsOnChain
    Oct 21, 2023
    👋GM everyone, 🚀The QuillCTF Dubai Challenges are live for 24 hours of the competition! ✅Add the solutions files for individual challenges in a zipped folder to submit your solutions!
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    1.8K01.8K
  • user avatar
    billh
    @hibillh
    Mar 16, 2024
    Can't get any closer than that 🤯 @kalos_security
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    1.9K01.9K
  • user avatar
    billh
    @hibillh
    Feb 11, 2019
    Replying to @officialbat419
    Hey
  • user avatar
    billh
    @hibillh
    Feb 28, 2022
    Received 401 when sending tx with metamask, thought my ledger is broken but the broken one turn out to be Arbitrum😑
  • user avatar
    billh
    @hibillh
    Dec 13, 2022
    Replying to @0xClandestine and @0xCygaar
    The balance is reduced before the call, so I think reentrancy attack does not work here
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