Another day, another multimillion-dollar heist in the ostensibly secure world of decentralized finance, where Bunni DEX—a relatively obscure cross-chain liquidity protocol—found itself $8.4 million lighter after sophisticated attackers exploited a critical flaw in its custom Liquidity Distribution Function.
The exploit, which simultaneously targeted Unichain and Ethereum networks, demonstrated how interconnected blockchain systems can amplify rather than mitigate systemic risks.
The attackers displayed remarkable precision, manipulating Bunni’s proprietary LDF through carefully sized trades that corrupted the protocol’s rebalancing calculations. This custom logic, integrated with Uniswap v4’s automated market maker mechanics, was supposed to track liquidity pool share ownership across trading ranges—a noble innovation that unfortunately became the protocol’s Achilles’ heel.
Innovation and vulnerability danced hand-in-hand as Bunni’s sophisticated liquidity tracking became the very mechanism of its downfall.
By subverting the AMM’s liquidity density assessments, the exploiters withdrew tokens far exceeding their entitled amounts, turning sophisticated financial engineering into an elaborate drainage system.
The theft’s execution was particularly brazen: approximately $6 million vanished via Unichain while another $2.4 million disappeared through Ethereum, with the Unichain proceeds subsequently bridged to Ethereum (because why leave evidence scattered across multiple chains?).
The cross-chain liquidity transfers lacked sufficient validation—an oversight that rendered multiple blockchains vulnerable simultaneously, like leaving every door in a house ajar because the security system was “cutting-edge.”
Bunni’s response followed the standard DeFi crisis playbook: immediate contract suspension, emergency security audits, and user advisories to withdraw remaining funds. The protocol, which had been operational since February 2025, demonstrated how even relatively new platforms could accumulate substantial value before critical vulnerabilities surfaced.
The stolen assets were predictably converted to Ethereum and laundered through privacy-focused bridges, following well-established criminal cryptocurrency protocols that seem increasingly sophisticated compared to the security measures they defeat. The attackers utilized Across Protocol to facilitate these conversions, leveraging the cross-chain bridge’s liquidity to efficiently transform their ill-gotten gains into more fungible assets.
The incident carries broader implications beyond Bunni’s immediate $50 million TVL—the $8.4 million loss represented roughly 17% of total secured value, a proportion that would make traditional financial institutions reassess their entire risk management framework.
The exploit exposed fundamental weaknesses in cross-chain liquidity management while highlighting the perils of deploying custom innovations without exhaustive battle-testing. The vulnerability demonstrates how a single code flaw can result in substantial financial evaporation within decentralized protocols.
As DeFi protocols race toward institutional adoption, incidents like Bunni’s serve as expensive reminders that complexity without corresponding security rigor remains a recipe for sophisticated theft.
