North Korea's Cryptocurrency Theft Tactics are Evolving, with DeFi Being a Prime Target

Less than three weeks after hackers linked to North Korea used social engineering to breach the crypto trading firm Drift, they appear to have carried out another major exploit with Kelp, a restaking protocol connected to LayerZero's cross-chain infrastructure. This attack suggests an evolution in North Korea-linked hackers' methods, as they now exploit fundamental assumptions in decentralized systems, not just seeking bugs or stolen credentials. The combined incidents of Drift and Kelp point to a more organized effort by North Korea to hijack crypto funds, indicating a sustained campaign rather than isolated breaches. According to Alexander Urbelis, Chief Information Security Officer and General Counsel at ENS Labs, 'This is not a series of incidents; it is a cadence. You cannot patch your way out of a procurement schedule.' More than $500 million was siphoned off in just over two weeks across these two exploits. The Kelp breach did not involve breaking encryption but rather manipulating data inputs to force the system to approve non-existent transactions. As David Schwed, COO of blockchain security firm SVRN, noted, 'The attack wasn’t about breaking cryptography; it was about exploiting how the system was set up.' A key issue was Kelp's reliance on a single verifier to approve cross-chain messages, a configuration choice that removed a critical safety layer. In response, LayerZero has recommended using multiple independent verifiers, akin to requiring multiple signatures on a bank transfer. However, some argue that LayerZero's default setup was to have a single verifier, raising questions about the balance between security and ease of setup. The fallout from the Kelp exploit has extended beyond the platform itself, affecting lending platforms like Aave that accepted impacted assets as collateral, turning a single exploit into a broader stress event. This incident also highlights the gap between the marketing of decentralization and its actual implementation, with Urbelis stating, 'Decentralization is not a property a system has. It is a series of choices. And the stack is only as strong as its most centralized layer.' As attackers focus on less visible layers like data providers or infrastructure, the risk may not be unknown vulnerabilities but known ones that are not fully addressed, making the gap between security recommendations and requirements both more exploitable and expensive to ignore.