What happened
On May 15, 2026, an attacker minted about 1.2 million unbacked wrapped ADS (wADS) on Ethereum through the Adshares bridge and sold them, taking about $628,000. The bridge's minter account issued three wrapTo() mints that cited transaction IDs that did not exist on the native Adshares chain, so no ADS had actually been locked to back them. The attacker sold the fake wADS on Ethereum for about 148.5 ETH and about $305,000 in USDC.
PeckShield later reported that the attacker returned 256 ETH, worth about $540,700 or roughly 86% of the stolen funds, to the Adshares deployer address. Adshares had not published a detailed postmortem at the time, so it is unconfirmed whether the minter key was compromised or an off-chain deposit check was fooled.
How it happened
- Each Adshares bridge mint on Ethereum is triggered by the bridge's minter account calling
wrapTo()on the wADS contract, citing a deposit transaction on the native Adshares chain. - On May 15, 2026, between 20:32 and 20:48 UTC, the minter account made three
wrapTo()calls citing native-chain transaction IDs that did not exist. They minted 99,999.93, 99,999.93 and 999,999.94 wADS to0x63e22Ce9Bde9bb8892a447258abfCaa4142f001B. - Nothing had been locked on the Adshares chain, so these tokens were unbacked.
- The attacker sold the wADS on Ethereum, taking out about 148.5 ETH and about $305,000 USDC, roughly $628,000 in total.
- The attacker later sent 256 ETH (about 86% of the proceeds) back to the project deployer.
Protocol details
Market Context at Time of Hack
Evidence
- report chrisdior on X: Adshares exploited for ~$628K (2026-05-16 20:50 UTC, via fxtwitter mirror) x.com
- report Crypto Exploits Report: May 2026 (Nominis) nominis.io
- analysis DeFiLlama defillama.com
- analysis Adshares Bridge Exploiter Returns 256 ETH After $628K Incident (CryptoAdventure, 2026-05-18) cryptoadventure.com
- analysis Blockscout: wADS token transfers (mints via wrapTo, blocks 25102963-25103043) eth.blockscout.com
- analysis Adshares: Cross-Chain Bridge Attacker Returns 86% of Stolen Funds (Bitget News, 2026-05-18) bitget.com
- analysis adshares.net page adshares.net adshares.net
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