The StakeDAO deployer private key (0x000755Fbe4A24d7478bfcFC1E561AfCE82d1ff62) was compromised. The attacker used it to reconfigure the LayerZero v2 OFT peer on the vsdCRV (Vote Boosted sdCRV) token contract, redirecting trust from the legitimate Ethereum-side vsdCRVOFTAdapter to an attacker-deployed malicious contract - then sent a forged cross-chain message that minted 5,446,744,073,709 vsdCRV (~5.4 trillion tokens).