# `BoldToken` initialization can be frontrun to silently mint/approve bold to an attacker Medium · Sherlock · CDP stablecoin · 3rd February, 2025 Finding M-1 of the Nerite security review. - Protocol: https://www.nerite.org/ - Report: /reports/nerite - Source: https://drive.google.com/file/d/1knlIgoEGv5x33n9mhTLRqJe8T55r3HCy/view --- ## Summary `BoldToken::initialize()` is frontrunnable. ## Vulnerability Detail `BoldToken::initialize()` is called seperately after the constructor, which means that if sent in different txs (depending on deployment scripts, it may be possible to mitigate if sent via a multicall), an attacker can frontrun the deployment, initialize the `BoldToken` to a malicious implementation, mint/approve `Bold` to their address and then set the implementation to `address(0)` so the script does not revert and the `BoldToken::initialize()` call succeeds. ## Impact Attackers mints/gets `Bold` for free. ## Code Snippet https://github.com/sherlock-audit/2025-02-nerite/blob/main/nerite/contracts/src/BoldToken.sol#L59-L72 https://github.com/superfluid-finance/protocol-monorepo/blob/1edc4ed3ddafa87d42c1155e870532e2a5a80470/packages/ethereum-contracts/contracts/upgradability/UUPSProxy.sol#L25-L29 ## Tool Used Manual Review ## Recommendation Use a multicall to deploy or move the `BoldToken::initialize()` logic to the constructor. --- Related findings: - [Malicious user may frontrun `GoodDollarExpansionController::mintUBIFromReserveBalance()` to make protocol funds stuck](https://0xsimao.com/findings/mento-frontrun-mint-ubi-stuck): Mento - [SuperToken._skipSelfMint silently skips minting, breaking custom SuperToken implementations](https://0xsimao.com/findings/superfluid-super-mint-skips-implementations): Superfluid Yield Backends - [DoSed liquidations as `PrizeVault::liquidatableBalanceOf()` does not take into account the `mintLimit` when the token out is the asset](https://0xsimao.com/findings/pooltogether-the-prize-layer-for-defi-liquidations-prize-liquidatable-mint): PoolTogether Prize Layer