The Drift Protocol hack was an unconventional attack that did not involve discovering a code vulnerability, cracking a private key, or exploiting a flash loan. Instead, an attacker utilized a legitimate Solana feature known as 'durable nonces' to deceive Drift's security council into pre-approving transactions that were executed weeks later, under a different context than what the signers had intended. This resulted in the loss of at least $270 million, with the entire process taking less than a minute to execute but over a week to set up.
Durable nonces are a Solana feature designed to override the expiring blockhash, a safety feature that prevents old transactions from being replayed, by replacing it with a fixed 'nonce' that keeps the transaction valid indefinitely. This feature is intended for legitimate uses, such as hardware wallets and institutional custody solutions that need to prepare and approve transactions without being forced to submit them within a short time frame. However, it creates a problem when transactions become indefinitely valid, allowing an attacker to get someone to sign a transaction that can be executed at a later time, without the signer's ability to revoke their approval. The attacker exploited this feature by obtaining two signatures from Drift's Security Council members, which were then used to execute malicious administrative transfers, giving the attacker full control of Drift's protocol-level permissions and allowing them to introduce a fraudulent withdrawal mechanism to drain the vaults.
On-chain researchers tracked the stolen funds in real-time, which totaled roughly $270 million across dozens of tokens, including JPL, USDC, and wrapped bitcoin. The primary drainer wallet was funded eight days before the attack and remained inactive until execution day.
The stolen funds were transferred to intermediary wallets and eventually moved to Ethereum addresses via a cross-chain bridge. The attack highlights the dangers of social engineering and operational security failures in DeFi protocols, particularly when it comes to the use of durable nonces, which can be difficult to defend against without fundamentally changing how multisig approvals work on Solana.