# Performance and management fees could round up to protect the protocol Low/Info · Blackthorn · Curated yield vaults · 13th August, 2025 Finding L-2 of the Morpho Vault V2 security review. - Protocol: https://morpho.org/ - Report: /reports/morpho-vault-v2 - Codebase: https://github.com/0xsimao/vault-v2/tree/ce661d820fb29307981f75eb42393db1c6e42758 - Source: https://github.com/morpho-org/vault-v2/blob/main/audits/2025-09-15-blackthorn.pdf --- ## Summary `VaultV2::accrueInterestView()` [rounds down](https://github.com/sherlock-audit/2025-08-morpho-vault-v2-aug-13th/pull/25/files#diff-b9b86210e027003894f79227889d79167f92c0aa2b2a1b0291f4606002e22540R589-R596) when applying the perfomance and management fees, leading to reduce interest payments for the protocol. ## Vulnerability Detail Since the Vault uses a decimal offset to always have 18 decimals, the difference should be negligible, but it is something to keep in mind, especially as gas prices keep decreasing and $WBTC price keeps increasing. For this reason protocols often round up when calculating fees, though it may not be necessary in this case. ## Impact Wei interest loss. ## Code Snippet https://github.com/sherlock-audit/2025-08-morpho-vault-v2-aug-13th/pull/25/files#diff-b9b86210e027003894f79227889d79167f92c0aa2b2a1b0291f4606002e22540R589-R596 ## Tool Used Manual Review ## Recommendation Consider rounding up, though the impact is negligible here. --- Related findings: - [Oracle fees should be payed upfront to protect the protocol from failed performeUpkeep() calls](https://0xsimao.com/findings/ostium-oracle-fees-upfront-performe): Ostium