ethereum is a common ethereum structs for Rust. Prior to ethereum crate v0.18.0, signature malleability (according to EIP-2) was only checked for "legacy" transactions, but not for EIP-2930, EIP-1559 and EIP-7702 transactions. This is a specification deviation. The signature malleability itself is not a security issue and not as high of a risk if the ethereum crate is used on a single-implementation blockchain. This issue has been patched in version v0.18.0. A workaround for this issue involves manually checking transaction malleability outside of the crate, however upgrading is recommended.
The product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product.