Hyperbridge has sharply revised the cost of its April 13 exploit, saying the real damage was about $2.5 million rather than the initial $237,000 estimate. The update matters because the loss was not only larger than first believed, but large enough to expose how quickly a cross-chain incident can outgrow early assessments once forensic work expands across multiple networks.
The bridge operator said the revised figure followed a deeper investigation spanning Ethereum, Base, BNB Chain and Arbitrum. That wider scope helped clarify the true path of the exploit and the actual proceeds realized by the attacker, underscoring that cross-chain breaches are often harder to size in real time than single-chain attacks.
A Verification Flaw Turned Into a Multi-Stage Breach
Early reports on April 13 described the incident as involving the minting of nearly 1 billion bridged DOT tokens, a detail that initially fueled confusion and even led some observers to dismiss the event as a prank. Hyperbridge later rejected that narrative and, on April 16, publicly confirmed that the exploit was real, material and far more serious than the first estimate suggested.
According to the project’s post-mortem, the attacker exploited a weakness in the Merkle Mountain Range proof verification logic inside the Token Gateway contract. The breach unfolded in two stages: first, about 245 ETH was extracted, and then almost 1 billion bridged DOT tokens were minted without authorization and sold into available decentralized exchange liquidity. In practical terms, the exploit was driven by a verification failure at the heart of the bridge’s trust model.
Recovery Efforts Now Depend on Exchange Coordination
Hyperbridge said forensic tracing identified a significant share of the proceeds at a Binance deposit address, and the team is now working with Binance’s compliance unit and law enforcement in an effort to freeze and recover funds. That makes centralized exchange coordination one of the most important remaining levers for limiting the final financial impact of the attack.
The Token Gateway will remain paused until the vulnerability is fixed, independently audited and additional safeguards are in place. Hyperbridge has also outlined a compensation plan under which affected users could receive native BRIDGE tokens if direct asset recovery proves insufficient, with a projected disbursement timeline around April 13, 2027. That response shows the project expects the operational and financial consequences of the exploit to extend well beyond the immediate breach window.
The Incident Raises Broader Compliance and Custody Questions
The case offers a clear procedural lesson. Multi-chain exploits require chain-by-chain tracing, detailed incident timelines and faster escalation paths when stolen funds reach centralized venues. In that sense, the real compliance burden begins after the exploit, when firms must translate fragmented on-chain evidence into actionable reporting and recovery efforts.
The jump from a $237,000 estimate to roughly $2.5 million also highlights how misleading early loss numbers can be in bridge attacks. When assets move across multiple chains and touch centralized exchanges, both forensic complexity and jurisdictional risk increase rapidly, making accurate loss assessment as much a compliance and coordination challenge as a technical one.