Manual Review

A thorough line-by-line review was conducted on the codebase to identify potential malfunctions and vulnerabilities in the V4 Bridge implementation of Sovryn.

As the project at hand implements a cross-chain bridge, intricate care was put into ensuring that the flow of funds within the system conforms to the specifications and restrictions laid forth within the protocol's specification.

We validated that all state transitions of the system occur within sane criteria and that all rudimentary formulas within the system execute as expected. We pinpointed multiple medium-level discrepancies within the system which could have had severe ramifications to its overall operation, however, they were conveyed ahead of time to the Sovryn team to be promptly remediated.

Additionally, the system was investigated for any other commonly present attack vectors such as re-entrancy attacks, mathematical truncations, logical flaws and ERC / EIP standard inconsistencies. The documentation of the project was satisfactory to a certain extent, however, we strongly recommend the documentation of the project to be expanded at certain complex points such as the exact nature of the two execution paths within the bridge's transfer acceptance function.

A total of 20 findings were identified over the course of the manual review of which 17 findings concerned the behaviour and security of the system. The non-security related findings, such as optimizations, are included in the separate Code Style chapter.

The finding table below enumerates all these security / behavioural findings: