Symbiosis Bridge Paused After More Than 40 Billion Fake Bitcoin Units Were Minted
Key Takeaways
- •Symbiosis has recovered about 15 bitcoin after an exploit of its native Bitcoin bridge, and the bridge remains paused while the protocol completes its accounting of the incident.
- •Blockchain security firm Blockaid estimated the attackers generated about $336,000 in proceeds, although Symbiosis said this figure should not be treated as the final loss amount.
- •The exploit minted roughly 2^62 raw syBTC, with a stated face value of about 46.1 billion, to a newly created wallet on BNB Chain, and the same beneficiary sold approximately 4.39 WBTC on Uniswap V4 on Ethereum.
- •Symbiosis offered a 20% bounty for the return of the stolen funds, with the recovery window set to end on September 13, 2026.
- •The protocol is contacting affected liquidity providers and building a compensation framework, but it has not yet specified eligibility criteria, calculation methods, or payment timelines.
Cross-chain protocol Symbiosis has recovered about 15 bitcoin after an exploit of its native Bitcoin bridge, but affected liquidity providers are still waiting for details about their losses and potential compensation.
The bridge remains paused while Symbiosis completes its accounting of the incident. Blockchain security firm Blockaid estimated that the attackers generated about $336,000 in proceeds. Symbiosis, however, said the figure should not be treated as the final loss.
Blockaid described the scale of the exploit in a report:
Signed BridgeV2 receive minted ~2^62 raw syBTC (8 decimals; face value ~46.1B) to a fresh EOA; same beneficiary dumped ~4.39 WBTC on Ethereum Uni V4.
The report indicates that the Symbiosis Bridge system minted raw units of syBTC, the synthetic representation of Bitcoin, to a newly created externally owned account. The minted tokens had a stated face value of about 46.1 billion, representing trillions of fake Bitcoin units on BNB Chain. The same beneficiary then sold approximately 4.39 WBTC through Uniswap V4 on Ethereum.
Symbiosis offered a 20% bounty for the return of the stolen funds, with the recovery window ending on September 13, 2026. The protocol said it would publish confirmed loss figures and additional details after completing its investigation.
The protocol also said it was contacting affected liquidity providers directly and developing a compensation framework. Eligibility criteria are expected to be announced later. Symbiosis has not yet specified who will qualify, how compensation will be calculated, or when payments could begin.
The incident underscores the risks faced by liquidity providers in cross-chain systems, where recovering assets does not necessarily mean that affected users will be fully compensated.
Source: BitcoinKE
