MultiversX's multisig-improved (repository: mx-multisig-and-modules) reference implementation of their on-chain multisig smart contract system contains a vulnerability where a missing independent authorization check allows any account with the Proposer role to perform explicitly barred actions. This vulnerability allows the Proposer role to move funds alone, draining 100% of a contract's EGLD/ESDT balance in two transactions with zero signatures.

Impact Metachain cannot process a cross-shard miniblock. An invalid transaction with the wrong username on metachain is not treated correctly on the metachain transaction processor. This is strictly a processing issue that could have happened on MultiversX chain. If an error like this had occurred, the metachain would have stopped notarizing blocks from the shard chains. The resuming of notarization is possible only after applying a patched binary version. Patches Introduce processIfTxErrorCrossShard for metachain transaction processor.

Workarounds No

References No

mx-chain-go is the official implementation of the MultiversX blockchain protocol, written in golang. When executing a relayed transaction, if the inner transaction failed, it would have increased the inner transaction's sender account nonce. This could have contributed to a limited DoS attack on a targeted account. The fix is a breaking change so a new flag RelayedNonceFixEnableEpoch was needed. This was a strict processing issue while validating blocks on a chain. This vulnerability has been patched in version 1.4.17.