How DPRK Hackers Use Cross-Chain Crypto Laundering to Evade Detection

North Korean hackers aren’t just stealing crypto-they’re rewriting the rules of how money moves online. In 2025, a single attack on Bybit stole over $1.5 billion, making it the biggest crypto heist in history. But the real story isn’t the amount. It’s how they got away with it. By hopping between blockchains-Ethereum, Bitcoin, Tron, Solana, and more-they turn what should be a clear trail into a maze. And law enforcement is barely keeping up.

Why Cross-Chain Laundering Works

Blockchain was supposed to be transparent. Every transaction is public. So how do hackers hide billions? The answer is cross-chain laundering. Instead of moving stolen funds within one network, they convert them across multiple chains using bridges like Avalanche Bridge and Ren Bridge. Each conversion breaks the visual link between the original theft and the final destination.

Think of it like cashing a stolen check at five different banks, each in a different country. No single bank sees the full picture. That’s exactly what DPRK hackers do. They start with Ethereum tokens, swap them to Tron, then convert to Bitcoin, then to BTTC, and finally to a new wallet on a lesser-known chain like Cronos or Moonbeam. By the time analysts catch up, the trail is cold.

The Lazarus Group and Their Playbook

The main force behind these attacks is the Lazarus Group, a state-sponsored hacking unit tied to North Korea’s Reconnaissance General Bureau. They don’t just hack-they plan. Their operations follow a clear pattern:

1. Target a centralized exchange or high-net-worth individual using phishing or social engineering
2. Drain wallets in seconds, often before anyone notices
3. Send funds to freshly created addresses under their control
4. Use cross-chain bridges to convert assets across networks
5. Flood the system with hundreds of micro-transactions to overwhelm tracking tools
6. Hold the converted Bitcoin for months, waiting for the right moment to cash out

This isn’t random chaos. It’s precision engineering. TRM Labs found that over 9,500 BTC have flowed through the Avalanche Bridge alone since 2022. That’s not a glitch. That’s a strategy.

Why Mixers Are Out, Cross-Chain Bridges Are In

A few years ago, hackers relied on crypto mixers-services like Tornado Cash and Wasabi Wallet-that blended stolen coins with others to hide their origin. But governments cracked down. Tornado Cash was sanctioned. Mixers got seized. So North Korea changed tactics.

Cross-chain bridges became the new go-to. Why? Because they’re legal, decentralized, and widely used. No one shuts down a bridge because it’s a protocol, not a company. Hackers exploit this. They use the same tools ordinary users rely on to move assets between chains-except they do it at scale, with automation, and without leaving a paper trail.

Elliptic reported a 111% spike in funds flowing through cross-chain services between 2023 and 2024, almost all of it tied to DPRK-linked wallets. Meanwhile, mixer usage dropped sharply. The hackers didn’t stop laundering-they upgraded.

The Bybit Heist: A New Benchmark

The February 2025 Bybit breach wasn’t just big-it was a turning point. Hackers stole over $1.5 billion in a single attack, more than all of North Korea’s crypto theft in 2023 combined. What made it different?

They didn’t just move funds. They flooded the system. Within hours, hundreds of transactions raced across Ethereum, Tron, Bitcoin, and BTTC. Analysts were overwhelmed. Exchanges froze accounts. But by the time investigators sorted through the noise, the money had already been converted into Bitcoin and parked in long-term wallets.

Nick Carlsen from TRM Labs, a former FBI crypto expert, called it the “flood the zone” technique. It’s not about hiding one transaction. It’s about drowning every tracker in data. The goal isn’t to disappear-it’s to make tracking impossible by volume.

Who’s Getting Targeted Now?

The old targets-exchanges like Binance, Coinbase, and Kraken-are still hit. But the smartest attacks now focus on people. High-net-worth crypto holders. Executives. Even influencers.

Why? Because their security is weak. They use simple wallets. They click phishing links. They reuse passwords. Elliptic says the weakest link in crypto security isn’t the code-it’s the human.

Hackers now pose as recruiters offering fake crypto jobs. They send fake invoices. They hack Twitter accounts to impersonate trusted figures. Once they get a private key, they drain the wallet and start the cross-chain laundering process. No exploit needed. Just deception.

How Analysts Are Fighting Back

Blockchain analytics firms didn’t sit still. TRM Labs launched TRM Phoenix in 2022-the first tool that automatically traces funds across chains. Chainalysis and Elliptic followed with similar tools. Now, investigators can map a transaction from Ethereum to Tron to Bitcoin in one dashboard.

The FBI has also stepped up. In 2023, they published a list of known Bitcoin addresses linked to Lazarus Group. Exchanges were asked to block them. Some did. Others didn’t. The result? A partial slowdown-but not a stop.

The problem? North Korea has more time, more resources, and no fear of jail. Their hackers work from inside the country, shielded by state protection. They don’t need to run. They just need to keep stealing.

Why This Isn’t Just a Crypto Problem

This isn’t about lost coins. It’s about nuclear weapons.

A 2024 UN report confirmed what intelligence agencies have suspected: North Korea’s weapons program is funded by cybercrime. The Biden administration estimates that nearly half of the DPRK’s foreign currency comes from crypto theft. That’s not a side hustle. It’s state policy.

The $2 billion stolen in 2025 didn’t vanish into thin air. It’s being used to buy missile parts, fuel for submarines, and components for nuclear warheads. Every cross-chain swap, every bridge transaction, every converted Bitcoin is directly tied to global security threats.

The Arms Race Is Just Starting

We’re in a crypto-laundering arms race. As tracking tools improve, North Korea adapts. They’re now creating their own tokens on obscure chains to launder money. They’re using refund addresses to redirect funds to fresh wallets. They’re even testing AI-driven transaction generators to automate obfuscation.

The latest tactic? Holding Bitcoin for months after conversion. In past attacks, hackers cashed out fast. Now, they wait. Why? Because liquidating $1 billion in Bitcoin all at once would crash the market-and draw attention. Instead, they slowly move it through over-the-counter (OTC) desks in Asia, using shell companies and intermediaries.

This isn’t the end of the story. It’s the next chapter.

What’s Next?

The next wave will likely involve DeFi protocols. Hackers are already testing exploits on lending platforms and yield aggregators that span multiple chains. If they can steal from a single DeFi pool and convert the funds across ten blockchains before anyone reacts, the scale of theft could hit $5 billion in a single operation.

Governments are talking about regulating cross-chain bridges. But that’s like trying to regulate the internet. You can’t shut down a protocol without breaking the whole system.

The real solution? Better collaboration. Exchanges need to share threat data faster. Regulators need to act before attacks happen-not after. And users? They need to stop treating crypto like cash in a sock drawer.

The money is moving. The hackers are winning-for now. But if the world doesn’t get serious about tracing and blocking these flows, the next stolen billion won’t just fund a weapons program. It could fund something far worse.