An attacker drained Cascade's CLS vault on Arbitrum for ~$1.34M USDC and laundered funds Arbitrum to Solana to Ethereum via Relay Protocol, converting to DAI to evade a Circle USDC freeze.
On July 16, 2026, Cascade — a Polychain- and Variant-backed Arbitrum perpetuals platform — was exploited for approximately $1.34M USDC when an attacker drained the protocol's CLS (Cascade Liquidity Source) vault. The CLS vault held the protocol's liquidity backing for the perps platform, and the attacker was able to extract the vault's USDC reserves through a sequence of unauthorized withdrawals that bypassed the vault's intended access controls.\n\nThe exploit targeted the CLS vault directly rather than the perps trading layer, allowing the attacker to extract the underlying liquidity without needing to manipulate market prices or open leveraged positions. Once the USDC was extracted on Arbitrum, the attacker immediately began a cross-chain laundering chain designed to evade the predictable Circle USDC freeze that follows major stablecoin thefts.\n\nThe attacker bridged the stolen USDC from Arbitrum to Solana using Relay Protocol, a cross-chain intent-based bridge that allows rapid asset movement between chains without the latency of traditional lock-and-mint bridges. From Solana, the funds were bridged again to Ethereum via Relay Protocol and then swapped from USDC into DAI through decentralized exchanges. The conversion to DAI was a deliberate anti-freeze measure: while Circle can freeze USDC at any holder address, DAI is a decentralized stablecoin with no central issuer freeze capability, making the funds effectively immune to the standard post-hack recovery lever.
Funds were laundered across three chains in rapid succession: Arbitrum to Solana to Ethereum, both cross-chain hops executed via Relay Protocol to minimize bridge latency. On Ethereum, the USDC was swapped for DAI through decentralized exchanges specifically to evade a Circle USDC freeze, since DAI has no central issuer capable of freezing balances. The multi-chain path and the DAI conversion indicate a sophisticated laundering strategy designed to defeat the standard stablecoin freeze response. No recovery has been reported.
N/A