Blockstream informed that the vulnerability has been fixed, and it is safe to return 4,000 BTC

According to Bitcoin News, Blockstream has notified "white hat" hackers that the vulnerability has been fixed, and 4,000 BTC can be safely returned. The hacker, who previously extracted about 4,000 BTC from the Liquid network, expressed willingness to return the funds but needed to wait for the vulnerability to be fixed. The entire negotiation process was conducted publicly through Bitcoin OP_RETURN messages.

The hacker initially proposed to return "most" of the BTC but later changed their stance, requesting that the vulnerability be fixed first: "Please fix the vulnerability first. The latest submitted code puts the chain at risk. Ensure that every node has been patched, and then we will confirm the fix and safely return the funds."

The hacker also sent encrypted details of the vulnerability to Blockstream. About two hours ago, Blockstream responded with a PGP-signed OP_RETURN message: "The cross-chain bridge nodes have been patched and can safely return the funds." Currently, 3,998.5 BTC remains under the hacker's control.