Ethereum’s ERC-8424 draft would give RWA issuers forced transfers over encrypted balances

A proposed Ethereum standard designated as ERC-8424 entered the review phase on Friday. Under this proposal, creators of tokenized real-world assets (RWAs) would gain the capability to forcibly transfer assets even when their amounts remain encrypted.

OpenZeppelin developer Aryeh Greenberg, who goes by the handle arr00, submitted the pull request within the ethereum/ERCs repository.

ERC-8424 introduces two public checks and three private functions to ERC-7984

ERC-8424 expands upon ERC-7984, an existing Ethereum standard designed for private tokens that keep asset values stored as encrypted pointers.

Additionally, the draft proposal introduces a pair of plaintext eligibility validations, a confidential verification method to determine if a specific transfer is permitted, a confidential figure indicating the spendable portion of a balance, and a forced transfer mechanism restricted to authorized entities.

Calculations for the spendable amount must factor in issuer-imposed freezes, lockup periods, vesting timelines, and pledged holdings. While the proposal sets boundaries around minting, burning, pausing, and freezing operations, it leaves the specific implementation details unspecified.

Regulations governing transfer permissions and transfer limits are also included. The text explicitly notes that issuers might occasionally need to relocate assets independently of a holder’s approval.

The documentation notes that these functions are already handled for tokens featuring public balances by ERC-3643 and ERC-7943.

A reviewer highlights a 64-call vulnerability exposing a holder’s encrypted balance

On Friday morning, community member zexoverz identified a flaw during discussions on the Ethereum Magicians forum thread.

Because the transfer validation and spendable-balance functions lack caller restrictions, any user can inspect another account’s details.

According to zexoverz, a binary search can successfully uncover a 64-bit encrypted balance within a maximum of 64 calls, provided the caller possesses the ability to decrypt the output.

Furthermore, zexoverz noted that the spendable-balance function would expose the account balance in a single call.

Pointing out that OpenZeppelin’s existing ERC7984Freezable implementation restricts visibility solely to the account holder, zexoverz requested that this restriction be incorporated into the specification.

Because balance caps and vesting schedules rely on specific amounts, zexoverz explained that a failed transfer would leak information precisely as cautioned against in the “Disclosure through reverts” section, bypassing any need for decryption.

ERC-8424 remains in draft status and requires final review from an Ethereum editor—specifically g11tech, jochem-brouwer, samwilsn, or xinbenlv.

On Friday, abcoathup assigned the number 8424 to the draft and updated the accompanying forum thread title accordingly.

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