In a brazen maneuver that has sent ripples through the cryptocurrency community, a hacker behind the $4.67 million exploit of Voltage Finance has resurfaced, moving around $182,000 worth of stolen Ether into Tornado Cash—a notorious crypto mixer. This move, identified by blockchain security firm CertiK, marks a significant development in the saga that began in March 2022, when the decentralized finance (DeFi) lending protocol fell victim to a sophisticated reentrancy attack exploiting a vulnerability in the ERC677 token standard.
Unraveling the Exploit
The attack on Voltage Finance, a platform once heralded for its innovative lending solutions, exploited a “built-in callback function” in the ERC677 token standard. This allowed the hacker to drain the platform’s lending pool with alarming efficiency. The breach resulted in the theft of various cryptocurrencies, including USDC, Binance USD, wrapped Bitcoin, and Ethereum, causing a substantial stir among users and investors alike.
Fast forward to May 2025, and the hacker’s recent activity has reignited the conversation around security in the DeFi space. CertiK’s disclosure of the Ether transfer—traced back to an address used in the original heist—highlights the ongoing challenges in tracking and recovering stolen crypto assets. The address had lain dormant since November, with its last transaction recorded 166 days ago, according to Etherscan data.
The Tornado Cash Connection
Tornado Cash has long been a thorn in the side of blockchain sleuths and regulators. Its capability to obfuscate transaction trails makes it a go-to tool for hackers looking to launder stolen funds. The movement of 100 ETH through this mixer not only complicates recovery efforts but also raises questions about the efficacy of current blockchain monitoring and intervention strategies. This situation echoes the complexities faced by other platforms, as seen in Movement Labs’ recent challenges amid their token-dumping scandal.
“The use of mixers like Tornado Cash is a significant hurdle in our efforts to trace and recuperate stolen assets,” noted a blockchain security expert who wished to remain anonymous. “This incident underscores the need for more robust surveillance and deterrent measures within the crypto ecosystem.”
A Broader Context of Crypto Vulnerabilities
Voltage Finance’s woes didn’t end with the 2022 exploit. In March 2025, the platform suffered another breach—this time targeting its Simple Staking pools, resulting in a further $322,000 loss. The protocol’s attempts to negotiate with the attacker, offering a $50,000 bounty, and its proactive measures, such as revoking access and filing police reports, reflect the ongoing cat-and-mouse game between DeFi platforms and malicious actors.
Moreover, the current landscape of cryptocurrency security paints a troubling picture. April saw crypto losses soar by 1,163%, largely due to a single, staggering theft of 3,520 Bitcoin through advanced social engineering. Excluding this outlier, crypto losses still marked a 21% increase from March, underscoring an escalating trend in DeFi vulnerabilities. For further insights into the industry’s struggles with security breaches, see our coverage of Movement’s token-dump scandal.
However, it’s not all doom and gloom. The swift recovery of over $18 million by KiloEx and the ZKsync Association’s retrieval of $5 million post-incident suggest that while the industry grapples with security challenges, there are also promising signs of resilience and adaptation.
What Lies Ahead?
The Voltage Finance exploit and subsequent Ether transfer to Tornado Cash highlight the ongoing and evolving threats in the DeFi landscape. As the crypto community digests these events, the pressing question remains: how can platforms better safeguard their protocols against such sophisticated attacks?
While the answers are far from simple, the path forward seems to hinge on a combination of technological innovation, cross-industry collaboration, and perhaps, regulatory advancements. As stakeholders ponder these challenges, one thing is clear—the need for enhanced security measures and swift response mechanisms has never been more critical.
The unfolding story of Voltage Finance’s exploits serves as a potent reminder of the high stakes in the world of decentralized finance, where the interplay of innovation and vulnerability continues to shape the future of digital assets.
Source
This article is based on: Voltage Finance exploiter moves $182K in ETH to Tornado Cash
Further Reading
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Steve Gregory is a lawyer in the United States who specializes in licensing for cryptocurrency companies and products. Steve began his career as an attorney in 2015 but made the switch to working in cryptocurrency full time shortly after joining the original team at Gemini Trust Company, an early cryptocurrency exchange based in New York City. Steve then joined CEX.io and was able to launch their regulated US-based cryptocurrency. Steve then went on to become the CEO at currency.com when he ran for four years and was able to lead currency.com to being fully acquired in 2025.
