Reach out for an audit or to learn more about Macro
or Message on Telegram

thirdweb A-17

Security Audit

April 23rd, 2024

Version 1.0.0

Presented by 0xMacro

Table of Contents


This document includes the results of the security audit for thirdweb's smart contract code as found in the section titled ‘Source Code’. The security audit was performed by the Macro security team on March 18, 2024.

The purpose of this audit is to review the source code of certain thirdweb Solidity contracts, and provide feedback on the design, architecture, and quality of the source code with an emphasis on validating the correctness and security of the software in its entirety.

Disclaimer: While Macro’s review is comprehensive and has surfaced some changes that should be made to the source code, this audit should not solely be relied upon for security, as no single audit is guaranteed to catch all possible bugs.

Overall Assessment

The following is an aggregation of issues found by the Macro Audit team:

Severity Count Acknowledged Won't Do Addressed
Code Quality 5 5 - -

thirdweb was quick to respond to these issues.


Our understanding of the specification was based on the following sources:

Source Code

The following source code was reviewed during the audit:

We audited the following contract within this repository:

Contract SHA256


Note: This document contains an audit solely of the Solidity contracts listed above. Specifically, the audit pertains only to the contracts themselves, and does not pertain to any other programs or scripts, including deployment scripts.

Issue Descriptions and Recommendations

Click on an issue to jump to it, or scroll down to see them all.

Security Level Reference

We quantify issues in three parts:

  1. The high/medium/low/spec-breaking impact of the issue:
    • How bad things can get (for a vulnerability)
    • The significance of an improvement (for a code quality issue)
    • The amount of gas saved (for a gas optimization)
  2. The high/medium/low likelihood of the issue:
    • How likely is the issue to occur (for a vulnerability)
  3. The overall critical/high/medium/low severity of the issue.

This third part – the severity level – is a summary of how much consideration the client should give to fixing the issue. We assign severity according to the table of guidelines below:

Severity Description

We recommend the client must fix the issue, no matter what, because not fixing would mean significant funds/assets WILL be lost.


We recommend the client must address the issue, no matter what, because not fixing would be very bad, or some funds/assets will be lost, or the code’s behavior is against the provided spec.


We recommend the client to seriously consider fixing the issue, as the implications of not fixing the issue are severe enough to impact the project significantly, albiet not in an existential manner.


The risk is small, unlikely, or may not relevant to the project in a meaningful way.

Whether or not the project wants to develop a fix is up to the goals and needs of the project.

Code Quality

The issue identified does not pose any obvious risk, but fixing could improve overall code quality, on-chain composability, developer ergonomics, or even certain aspects of protocol design.


Warnings and things to keep in mind when operating the protocol. No immediate action required.

Gas Optimizations

The presented optimization suggestion would save an amount of gas significant enough, in our opinion, to be worth the development cost of implementing it.

Issue Details


Compact signatures are not supported

Protocol Design
Quality Impact

Reference: SeaportEIP1271.sol#L21

The isValidSignature functions only works with signatures consisting of 65 bytes. However, another form of signatures exists - the so called “compact” signatures - that only consist of 64 bytes (see ERC-2098).

As a result, the isValidSignature functions reverts for both Seaport bulk orders as well as standard signatures when a message has been signed using the compact signature scheme.

Remediations to Consider

Adapt the logic to support compact signatures.


Signature validation only works with Seaport 1.5

Quality Impact

Reference: SeaportOrderParser.sol#L74C15-L74C42

The current validation logic for bulk orders is only compatible with Seaport version 1.5. This is due to the domain separator being built from the version hash derived from the string "1.5":

 // Derive hash of the version string of the contract.
 versionHash = keccak256(bytes("1.5"));

Therefore, the current implementation does not support earlier versions or future versions. Although Seaport v1.5 is the latest deployed version, v1.6 was recently released. It is foreseeable that protocols will use version 1.6 or newer versions in the future.

Remediations to Consider

Adapt the logic in isValidSignature to accommodate different versions of seaport, as of now version 1.5 and 1.6 might be relevant. The differentiation can be made based on the address of the Seaport contract that calls the isValidSignature function.

Going forward, whenever a new version of seaport needs to be supported, ManagedAccountFactory can be upgraded to support those versions.


Comment the origin of SeaportOrderParser.

Quality Impact

Reference: SeaportOrderParser.sol

Most of the functions in SeaportOrderParser were copied over from Seaport’s Core repository, mainly from GettersAndDerivers and Verifiers contracts.

Remediations to Consider

Add appropriate comments to the respective functions to make it clear for potential readers (users, devs, auditors) where the code is coming from.


Use constant instead of literal

Best Practice
Quality Impact

Reference: SeaportEIP1271.sol#L31

The function isValidSignature uses the following if statement to differentiate between bulk orders and standard ECDSA signatures:

if (_signature.length > 65) {

However, instead of the literal 65 the constant ECDSA_MaxLength defined in SeaportOrderParser can be used.

Remediations to Consider

To improve readability, it is recommended to use constants instead of literals.


Improve testing

Quality Impact

Reference: SeaportEIP1271.t.sol

Currently, only a minimal test case is included that verifies the successful creation and fulfillment of a simple Seaport bulk order.

Remediations to Consider

Add additional test cases covering:

  • fulfilling a single order (instead of bulk orders)
  • include a offer item in the bulk order
  • etc.


Macro makes no warranties, either express, implied, statutory, or otherwise, with respect to the services or deliverables provided in this report, and Macro specifically disclaims all implied warranties of merchantability, fitness for a particular purpose, noninfringement and those arising from a course of dealing, usage or trade with respect thereto, and all such warranties are hereby excluded to the fullest extent permitted by law.

Macro will not be liable for any lost profits, business, contracts, revenue, goodwill, production, anticipated savings, loss of data, or costs of procurement of substitute goods or services or for any claim or demand by any other party. In no event will Macro be liable for consequential, incidental, special, indirect, or exemplary damages arising out of this agreement or any work statement, however caused and (to the fullest extent permitted by law) under any theory of liability (including negligence), even if Macro has been advised of the possibility of such damages.

The scope of this report and review is limited to a review of only the code presented by the thirdweb team and only the source code Macro notes as being within the scope of Macro’s review within this report. This report does not include an audit of the deployment scripts used to deploy the Solidity contracts in the repository corresponding to this audit. Specifically, for the avoidance of doubt, this report does not constitute investment advice, is not intended to be relied upon as investment advice, is not an endorsement of this project or team, and it is not a guarantee as to the absolute security of the project. In this report you may through hypertext or other computer links, gain access to websites operated by persons other than Macro. Such hyperlinks are provided for your reference and convenience only, and are the exclusive responsibility of such websites’ owners. You agree that Macro is not responsible for the content or operation of such websites, and that Macro shall have no liability to your or any other person or entity for the use of third party websites. Macro assumes no responsibility for the use of third party software and shall have no liability whatsoever to any person or entity for the accuracy or completeness of any outcome generated by such software.