The network validator found some unusual activity and prevented from the same.

Cross-chain protocols are continuing to face many challenges, with Synapse Bridge narrowly averting a multi-million exploit.

On Nov. 7,Synapse Bridge had announced on Discord they had prevented a hacker from draining approximately USD 8 million from the Avalanche Neutral Dollar (nUSD) Metapool.

The hacker had attempted to exploit a vulnerability using the bridge to transfer assets from Polygon (MATIC) to Avalanche (AVAX). 

While the Synapse is a cross-chain bridge designed to facilita swaps and transfers between a range of layer-one and layer-two protocols using an automated market maker (AMM).

Synapse Bridge mentioned: “Over the past 16 hours, we encountered and discovered a contract bug in the way that the AMM Metapool contracts handle virtual price calculations against the base pool’s virtual price.”

As soon as Synapse’s validators became aware of AMM’s

, the protocol paused its support for all chains and went offline. By shutting down the network, validators were able to collectively elect to reverse the transaction before it could be confirmed. In this way, the funds will ultimately not be minted to the attackers’ address on the destination chain.

“The validators will instead mint the nUSD back to the affected Avalanche LPs. All Avalanche nUSD LPs will be made whole, with no funds lost,” stated Synapse Bridge. The funds from the rejected transaction will be used to reimburse the affected liquidity providers after the full audit of the exploit is completed.