Symbiosis says recovered 15 BTC from bridge hack, offers 20% bounty

Cross-chain liquidity protocol Symbiosis said it recovered 15 Bitcoin, worth around $1.1 million, from a Bitcoin bridge exploit it suffered Friday.

Symbiosis said it recovered 15 Bitcoin (BTC) into a team-controlled multi-sig wallet and clarified that all routes remain operational, according to a Friday X post. The exploit affected Symbiosis’ native Bitcoin bridge, which remains paused.

The attacker’s address minted 46.1 billion unbacked tokens from the protocol’s Bitcoin bridge but realized net proceeds of 4.3 Wrapped Bitcoin (WBTC), worth $336,000, according to blockchain security company Blockaid, which flagged the exploit on Friday. The protocol has not specified how the recovered Bitcoin relates to the $336,000 in proceeds attributed to the attacker.

Symbiosis is now offering a 20% bounty to anyone who provides information that leads to asset recovery. The protocol initially offered a 20% white-hat bounty for the attacker to return the funds, but the deadline expired on Sunday. The protocol said it will reveal a compensation framework for affected liquidity providers.

DefiLlama clocked around $336,000 lost in the exploit, but the protocol has yet to disclose its final accounting of losses incurred.

Bridge exploits continue testing DeFi

In June, Secret Network suffered an “infinite mint” exploit that drained about $4.6 million from the protocol.

In May, the Verus-Ethereum bridge was drained in a forged cross-chain transfer exploit for 5,402 Ether, then worth about $11.6 million. The hacker returned 75% of the stolen funds and kept about 1,350 Ether, or $2.8 million, a day after the protocol offered it a 25% white-hat bounty.

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