Blockchain & Smart Contract Security Audit

The famous exploits of recent years were rarely simple reentrancy. They were subtle logic flaws: an accounting error that let someone withdraw more than they deposited, a price oracle that could be moved with a flash loan, a rounding difference that compounded into a fortune. These don’t show up in a scanner. They show up when an experienced auditor understands what the protocol is supposed to do and works out how to make it do something else.

DeFi protocols can be broken without a single line of buggy code, purely through economic manipulation: flash loans to distort a price, sandwich attacks, incentive designs that reward the wrong behaviour. We model these scenarios against your protocol’s actual mechanics, because in this space the money is the attack surface.

We start by understanding intent. What is the protocol meant to do, who can call what, where does value flow, and what would an attacker most want to achieve? A contract can be flawless against its spec and still be exploitable if the spec itself has a gap, so we scrutinise the design as well as the code.

The core of the audit is a human reading every line, function by function, tracing how state changes and where trust boundaries sit. This is where the serious findings come from, and it’s why depth of experience matters more than the number of tools on the shelf.

Tooling that supports the review

Alongside the manual work we run static analysers such as Slither, use fuzzing frameworks like Foundry and Echidna to hammer invariants with random inputs, and employ symbolic execution where it helps prove or disprove a property. The tools surface candidates; the auditor decides what’s real and what’s exploitable.

A finding is far more convincing with a working exploit behind it. Where a vulnerability allows it, we write a proof-of-concept against a fork of the target chain, demonstrating the drained funds or the broken invariant concretely rather than describing a theory. That leaves no room for “we don’t think that’s exploitable”.

We deliver findings ranked by severity with clear explanations and recommended fixes, then review your corrections once they’re made. An audit that ends at the report is only half done; the value is confirming the fixes are correct and haven’t introduced new problems.

The bug that started it all is still with us, now in subtler forms. Cross-function and read-only reentrancy catch teams who thought a single guard was enough. Any external call is a moment where control leaves your contract, and every one of them needs to be treated as hostile.

A protocol that trusts a single on-chain price source can be gamed by anyone able to move that price, and a flash loan lets an attacker move it with borrowed capital they repay in the same transaction. Well-chosen price feeds and manipulation-resistant design are among the most important things we check.

Missing or wrong access modifiers, initialisers that can be called by anyone, and admin functions with no timelock have all led to real losses. We map every privileged function and confirm that only the intended party can reach it, and that the intended party can’t quietly rug the protocol either.

Fixed-point maths, rounding, and the order of operations are a constant source of exploitable bugs. A rounding difference that seems trivial can be repeated thousands of times per block until it drains a pool. We check the maths as carefully as the logic.

The public mempool means anyone can see your users’ pending transactions and reorder or sandwich them for profit. Designs that don’t account for miner-extractable value and transaction ordering leak money to bots on every trade. We flag where your protocol is exposed and how to blunt it, whether through commit-reveal schemes, slippage protection or better sequencing assumptions.

Every finding with a severity rating, a clear technical explanation, the affected code, the potential impact in real terms, and a specific recommended fix. Where we built a proof of concept, it’s included so your developers can reproduce the issue exactly.

A concise overview for founders, investors and non-technical stakeholders on the overall security posture, the most serious issues, and whether the code is ready for the value you intend to put behind it.

A review of your fixes at no extra cost, and a final report suitable for publishing to your community, since a credible audit is something your users and investors will ask to see before they trust the protocol with their funds.

As the EU’s Markets in Crypto-Assets regulation takes hold, issuers and service providers face growing expectations around operational resilience and security. A documented audit supports that story and the due diligence that partners, exchanges and investors increasingly demand.

Beyond the contracts, the organisation running them still needs sound security. Where you also hold private keys, run infrastructure and handle user data, ISO 27001 and SOC 2 apply just as they would to any company, and our wider testing services cover that side too.