Summer.fi has reported a significant security breach involving its Lazy Summer USDC vaults, resulting in a loss of approximately $6.04 million. On July 6, an attacker exploited the vaults by manipulating their net asset value (NAV). This was achieved by injecting overvalued Silo tokens into an offline Ark, which was still factored into the NAV calculations. The attacker then extracted the funds in a single atomic transaction. The incident highlights vulnerabilities in the vault's pricing mechanisms, prompting Summer.fi to release a detailed post-mortem. The platform is currently investigating the breach and working on measures to prevent future occurrences.