An attacker exploited Hyperbridge’s Ethereum gateway contract to mint 1 billion fake bridged DOT tokens, but thin liquidity on the Ethereum side meant the massive token mint translated into just $237K in realized proceeds.
What Happened in the Hyperbridge Exploit on Ethereum
Polkadot confirmed it was aware of an issue affecting Hyperbridge’s Ethereum gateway contract. The exploit specifically targeted DOT tokens on Ethereum that were bridged through Hyperbridge, not the native Polkadot network itself.
According to a CertiK security alert, the attacker used a forged message to change the admin of the Polkadot token contract on Ethereum. With admin control seized, the attacker minted 1 billion fake bridged DOT tokens in a single transaction.
The distinction matters: these were ERC-20 representations of DOT on Ethereum issued through Hyperbridge, not native DOT on Polkadot. Transaction data from CertiK Skylens confirmed a balance change of 1,000,000,000 tokens tied to the exploit.
Why 1 Billion Fake DOT Produced Only About $237K
The mismatch between the billion-token mint and the roughly $237K in actual proceeds comes down to available liquidity. Bridged DOT on Ethereum had limited trading depth, so dumping a billion tokens into a shallow pool drained it almost immediately.
The exploit transaction showed a PoolManager ETH change of approximately 108.24 ETH, representing the total extractable value from the liquidity pool. No matter how many tokens the attacker minted, they could only pull out what the pool held.
This liquidity-cap dynamic is a detail most early coverage of the incident missed. The headline figure of 1 billion tokens sounds catastrophic, but the actual financial damage was constrained by the small footprint of Hyperbridge’s bridged DOT market on Ethereum. Similar dynamics have played out in past bridge exploits where tokenized assets on Ethereum carry far less liquidity than their native counterparts.
What the Exploit Means for DOT Holders and the Market
Polkadot stated that native DOT, the Polkadot network itself, and DOT bridged through other bridges all remained secure and unaffected. Hyperbridge was paused following the incident to prevent further exploitation.
DOT’s spot price still reacted to the news, falling from $1.23 to $1.17 as reports surfaced. At the time of research, DOT traded around $1.18, down roughly 4.33% over 24 hours, with 24-hour trading volume near $267.9 million.
The broader market backdrop amplified the sell pressure. The Fear & Greed Index sat at 12, deep in Extreme Fear territory, a sentiment environment where even isolated security incidents can trigger outsized price moves. Bitcoin’s recent hold at key support levels has not been enough to lift altcoin confidence, and DOT holders using non-Hyperbridge bridges or holding native DOT on Polkadot had no direct exposure to the exploit.
Hyperbridge has not yet published a full postmortem or confirmed the final root cause. One unconfirmed analysis, attributed to blockchain security firm Blocksec, suggested the exploit may have involved a Merkle Mountain Range proof replay vulnerability caused by missing proof-to-request binding, but the protocol has not verified this assessment.
For DOT holders, the practical takeaway is narrow: only users who held bridged DOT through Hyperbridge on Ethereum were affected. Those holding DOT natively or through other bridge infrastructure were not exposed. The incident underscores the persistent risk gap between native assets and their bridged representations, where a single contract vulnerability can undermine an entire wrapped token supply without touching the underlying chain.
Disclaimer: This article is for informational purposes only and does not constitute financial or investment advice. Cryptocurrency and digital asset markets carry significant risk. Always do your own research before making decisions.
