Blockchain Security Audit for Japan

Japan runs one of the most demanding digital asset supervision regimes in the world, and Japanese engagements reflect it: custody architecture, asset segregation, operational evidence and documentation quality carry as much weight as the code review itself.

ブロックチェーン・スマートコントラクトのセキュリティ監査 — 日本の取引所、発行体、事業会社向けに、スマートコントラクト監査、プロトコル監査、インフラ・鍵管理のセキュリティ評価を提供しています。報告書は英語で作成し、日本語での要約と説明会に対応します。

Blockchain security audits for Japan

Japanese buyers ask different questions from the rest of the market. Less "find us bugs before launch", more "demonstrate that this system is operated safely and prove it in a form our internal audit and our supervisor can examine". The technical depth has to be there, and the documentation discipline around it has to be there too, because the report will be read carefully by people whose job is to find gaps in it.

Custody is the centre of gravity. Japan's regime around exchange operations has long emphasised segregation of customer assets and heavy use of cold storage, and the practical consequence is that the highest-value review work is on key ceremony, wallet architecture, the boundary between hot and cold, withdrawal approval workflow and the operational discipline around each. We test those by running them, not by reading the procedure document.

Security tokens are the second area. Japan built a securities-law route for tokenized instruments earlier than most markets, and the resulting products are held to instrument standards rather than token standards: transfer restrictions must be enforceable, the register must reconcile, and issuer powers must be governed. That is precisely the shape of our tokenized securities work.

Practically, we work Japanese business hours for Japanese clients, deliver reports in English with a Japanese-language executive summary, and run the findings debrief with interpretation where the team prefers it. Documentation is written to be handed to internal audit without a translation layer of our own explanation.

What shapes security work in Japan

FSA supervision and the Payment Services Act

Crypto asset exchange service providers in Japan operate under registration with the Financial Services Agency, with expectations covering customer asset segregation, cold wallet management and operational risk governance. We assess whether the technical implementation supports the commitments made in that framework; interpretation stays with your counsel.

Security tokens under FIEA

Tokenized securities in Japan are handled under financial instruments regulation rather than the crypto asset regime, which places the enforceability of transfer restrictions, register integrity and issuer powers at the centre of the security review.

JVCEA self-regulatory expectations

The industry self-regulatory organisation maintains operational and security expectations that member firms are examined against. Engagements are scoped so findings and evidence map cleanly onto that examination.

Documentation and internal audit culture

Japanese institutions place unusual weight on evidence quality and traceability. We deliver methodology, scope statements, tester qualifications, evidence and remediation verification as standard rather than on request.

Regulatory references describe the general shape of a regime and are not legal advice. Requirements change; confirm your obligations with your own counsel and supervisor.

Clients we audit in Japan

How we work with Japan clients

How the engagement runs

  1. Scoping and threat modelling

    We fix a commit hash, agree the in-scope contracts and read your architecture docs, then build a threat model: who the actors are, what the trust boundaries are, and which invariants must never break. Nothing is reviewed against assumptions we have not written down.

  2. Manual review

    Line-by-line review by at least two auditors working independently, focused on authorisation, accounting, upgrade paths, external integrations and the gap between what the code does and what the documentation claims it does. Most critical findings come from this phase, not from tooling.

  3. Static and dynamic analysis

    Static analysers appropriate to the language, plus property-based fuzzing and invariant testing to push the system into states no unit test covers. Tooling is used to widen coverage, never to replace the manual pass.

  4. Exploit-path simulation

    Candidate findings are proven on a forked network with a working proof of concept. We report what an attacker can actually do and what it costs them, not a theoretical severity label.

  5. Reporting

    Every finding gets a severity rating, reproduction steps, the affected code, the impact in concrete terms and a specific remediation. You get a draft for discussion before anything is finalised.

  6. Fix review and re-test

    We re-test every remediation against the original proof of concept and check that the fix has not opened a new path. The final report is yours to publish.

What you receive

Blockchain security in Japan: frequently asked questions

Do you support Japanese-language deliverables?

Reports are written in English with a Japanese-language executive summary and finding titles, and debriefs can run with interpretation. Full-report translation can be arranged when internal audit requires it.

Do you understand Japanese exchange custody requirements?

Yes — segregation of customer assets, cold wallet architecture, the hot/cold boundary, key ceremony and withdrawal approval workflow are the core of most Japanese exchange engagements we run.

Can you audit security tokens issued under Japanese law?

Yes. Our tokenized securities work covers transfer-restriction enforceability, investor eligibility, register reconciliation and issuer powers, which is the shape a Japanese ST review takes.

Will you work in Japanese business hours?

Yes, for Japanese clients we schedule in JST. Critical findings are escalated the same day regardless of the hour.

Can you produce evidence for our internal audit and supervisor?

Yes. Documented scope, methodology, tester qualifications, per-finding evidence and verified remediation are standard deliverables on Japanese engagements.

What do you need from us to start an audit?

A repository or contract address, a commit hash to freeze the scope, whatever architecture or spec documentation exists, and a point of contact who can answer design questions. If documentation is thin we will write our understanding of the system back to you and ask you to confirm it — that step alone catches design-level bugs.

How long does an audit take?

A single token contract is 24–48 hours. A typical dApp or mid-sized protocol runs one to two weeks. Large DeFi systems, L2s, bridges and ZK circuits are scoped per project after we have seen the code. We will give you a fixed timeline with the quote, not an estimate that moves.

Security programmes by industry

Where else we work

Get a fixed quote in 24 hours

Send the repository and a commit hash through the contact form, message @bugtester25 on Telegram, or book a 30-minute scoping call. 200+ protocols audited · $4B+ secured · 0 hacks post-audit. Prefer email? info@safeedges.in.