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  • Questions for System Design Reviews

    2019-05-12

    Moving towards operationalizing system design reviews. What questions should a review team ask, or expect to be answered?

  • What is the Value-add of ssh-agent?

    2019-01-14

    The purpose of ssh-agent and observations how ssh-agent improves UX and security.

  • Fiat-Shamir Heuristic

    2018-09-22

    Overview and implementation of the Fiat-Shamir heuristic used to build signature schemes from interactive zero-knowledge proofs.

  • Building Lattice Reduction (LLL) Intuition

    2017-07-25

    My attempt to grok the Lenstra–Lenstra–Lovász (LLL) algorithm used for basis reduction.

  • Subgroup Confinement Attacks

    2017-01-14

    Subgroup confinement attacks can apply in offline and online contexts.

  • User-influenced Shell Commands Are Still Considered Harmful

    2016-12-06

    Non-obvious ways of getting code execution when testing code that uses user input to build shell commands.

  • The GGH Cryptosystem

    2016-11-23

    An introduction to lattice-based cryptography using the broken Goldreich–Goldwasser–Halevi (GGH) cryptosystem.

  • ASIS CTF 2016: RSA Write-up

    2016-09-18

    Breaking RSA with sequential prime key parameter generation.

  • Tokyo Westerns / MMA CTF: Twin Primes Write-up

    2016-09-01

    Decrypting RSA ciphertexts using correlated parameters.

  • Modifying IP Headers With netfilter

    2016-08-20

    Using netfilter to programmtically rewrite the source IP address of ICMP packets.

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