North Korea's Cryptocurrency Hacking Strategies Are Evolving, with DeFi Being a Prime Target

Barely three weeks after hackers linked to North Korea used social engineering to breach the crypto trading firm Drift, another significant exploit has been carried out against Kelp, a restaking protocol connected to LayerZero's cross-chain infrastructure. This attack suggests that North Korea-linked hackers are adapting their tactics, moving beyond exploiting bugs or stolen credentials to manipulating the fundamental assumptions underlying decentralized systems. The combined impact of these incidents points to a more organized effort by North Korea to siphon funds from the cryptocurrency sector. According to Alexander Urbelis, chief information security officer and general counsel at ENS Labs, 'This is not a series of isolated incidents; it's a cadence. You can't patch your way out of a procurement schedule.' More than $500 million was stolen across the Drift and Kelp exploits in just over two weeks, highlighting the escalating efforts by North Korea to hijack crypto funds. The Kelp breach did not involve breaking encryption or cracking keys; instead, attackers manipulated the data feeding into the system, forcing it to rely on compromised inputs and approve non-existent transactions. As Urbelis noted, 'A signed lie is still a lie. Signatures guarantee authorship; they do not guarantee truth.' This exploit was more about exploiting the system's setup than about breaking cryptography, as David Schwed, COO of blockchain security firm SVRN, pointed out. A key issue was the configuration choice to rely on a single verifier to approve cross-chain messages, which, while faster and simpler to set up, removes a critical safety layer. In response, LayerZero has recommended using multiple independent verifiers to approve transactions, akin to requiring multiple signatures on a bank transfer. However, some argue that LayerZero's default setup was to have a single verifier, underscoring the challenge of balancing security with ease of use. The fallout from the exploit has not been contained, as assets used across multiple platforms can spread problems. 'These assets are a chain of IOUs,' Schwed said, 'and the chain is only as strong as the controls on each link.' When one link breaks, others are affected, leading to wider stress events, such as lending platforms like Aave dealing with losses after accepting impacted assets as collateral. This incident also highlights the gap between the marketing of decentralization and its actual implementation. 'A single verifier is not decentralized,' Schwed said. 'It's a centralized decentralized verifier.' Urbelis emphasized that '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.' This means that even systems appearing decentralized can have weak points, particularly in less visible layers like data providers or infrastructure, which are increasingly the focus of attackers. The targeting of cross-chain and restaking infrastructure by groups like Lazarus reflects this shift, as these layers are critical, complex, and hold large amounts of value, making them attractive targets. The move towards targeting the 'plumbing' of the crypto industry—systems that connect everything together but are harder to monitor and easier to misconfigure—poses significant risks, especially as attackers adapt faster than known vulnerabilities can be fully addressed. The Kelp exploit did not introduce a new kind of weakness but showed how exposed the ecosystem remains to familiar ones, especially when security is treated as a recommendation rather than a requirement.