Blockaid withdraws BTTC bridge exploit alert after shutdown operation confirmed

Blockchain security firm Blockaid withdrew an earlier exploit alert involving the BitTorrent Chain [BTTC] Bridge. This came after determining that a $13.3 million asset drain was part of an authorized internal operation linked to the project’s planned bridge shutdown.

The incident unfolded within minutes on Tuesday after Blockaid’s monitoring system flagged suspicious on-chain activity that resembled a bridge compromise. 

Justin Sun later said the transactions were part of the completion of the BTTC Bridge Sunset Program, prompting Blockaid to revise its assessment.

Bridge activity initially resembled an exploit

Blockaid initially warned of a potential exploit on the BTTC Bridge after detecting approximately $13.3 million in assets. The assets included about 7,285 ETH and multiple ERC-20 tokens, leaving the bridge’s Ethereum predicate contracts.

According to the firm’s analysis, the BTTC bridge admin Safe executed a privileged proxy upgrade before an address received the CFO_ROLE on the upgraded RootChainManager. That address then called the withdrawAll[address[]] function to drain assets from the bridge contracts.

The sequence closely resembled the type of privileged activity commonly associated with bridge exploits. This led Blockaid to classify the event as a potential security incident while it investigated.

Justin Sun says transfers completed bridge sunset

Shortly after the alert, Tron founder Justin Sun replied publicly that the BTTC team had completed the BTTC Bridge Sunset Program.

Sun said the bridge shutdown had been finalized as part of an internal operational process. He added that all user funds remained safe and that users could continue depositing and withdrawing bridged assets through partner centralized exchanges. 

He also said the BitTorrent team would shift its focus to decentralized AI initiatives and to maintaining the BitTorrent decentralized protocol.

Blockaid subsequently updated its assessment, stating that the project team had approved the upgrade and asset transfers and were “part of internal operation, not an exploit.”

Shutdown had been announced weeks earlier

The clarification aligns with BitTorrent’s previously announced plan to retire the BTTC Bridge.

In an announcement published on June 12, the project said it would begin a phased shutdown of the bridge. It said it would close deposits from June 13 and complete all bridge withdrawals by June 18. 

Users were instructed to migrate bridged assets back to their native blockchains before the deadline. Also, the team said BTTC’s staking, validator operations, and broader network would remain unaffected.

The bridge’s closure forms part of a broader shift in the project’s roadmap, with BitTorrent directing users towards centralized exchange infrastructure for future cross-chain transfers.

Final Summary

• Blockaid initially flagged a potential $13.3 million BTTC Bridge exploit before determining the transactions were part of an authorized internal operation.
• The asset transfers were linked to the previously announced BTTC Bridge Sunset Program, which BitTorrent unveiled in June as part of its phased bridge shutdown.