Cryptographic System & Implementation Auditing
Strong algorithms, wired up wrong, protect nothing. I audit the wiring.
Nobody breaks AES. They break the code around it — the nonce reused, the key logged, the comparison that leaks timing, the random number that wasn't. Cryptographic failure is almost always an implementation failure, and that is exactly where I look.
I audit the whole construction: the protocol design, the library choices, the key lifecycle, and the embarrassing little details that turn a sound scheme into a decorative one. For systems where a crypto flaw is existential — wallets, messengers, vaults, auth — this is the review that has to be right.
- Protocol and handshake design review against known attack classes
- Key generation, storage, rotation, and destruction lifecycle audit
- Randomness and entropy-source verification
- Nonce, IV, and padding handling review
- Constant-time and side-channel (timing, cache) analysis
- Library selection and misuse assessment
- End-to-end and zero-knowledge construction verification
- Post-quantum readiness and migration planning
I read the code and the spec together, because the gap between them is where the bugs live. Findings are explained with the concrete attack they enable, not an abstract warning, so your engineers understand why it matters and how to fix it correctly rather than superficially.
Every engagement runs under a signed NDA and, where testing is involved, a Safe Harbor agreement. Legal and ethical, start to finish.
- A cryptographic audit report with each finding tied to a concrete attack
- A key-management and lifecycle assessment with corrective design
- A remediation and, where relevant, post-quantum migration roadmap
We use a vetted library — isn't that enough?+
A good library is necessary, not sufficient. Most real failures come from how the library is used: reused nonces, mishandled keys, leaked timing. That usage is exactly what the audit examines.
Can you review a zero-knowledge or E2E design?+
Yes. End-to-end, zero-knowledge, and multi-party constructions are core work — both the mathematical design and the implementation that has to honor it.
Hire me for Cryptographic System & Implementation Auditing.
Signed NDA and Safe Harbor on every engagement. Projects from five figures to nine. Discreet, relentless, done right.
I only do legal, ethical hacking — under a Safe Harbor contract and NDA.