ether.fi suffers 15.45 ETH loss in AtomicQueue exploit
ether.fi (ETHFI)
Editor:
Eugene Serbin
lookonchain.com reports that ether.fi was attacked, resulting in losses of approximately 15.45 ETH. SlowMist identified the root cause as a lack of access control for the `solver` parameter in the `solve()` function of the AtomicQueue contract. The contract did not verify that `solver == msg.sender`, nor did it check for signatures, registration, or authorization.
The attacker constructed a malicious AtomicRequest via the `updateAtomicRequest()` function and forced a victim address to act as the solver. Subsequently, the contract called `finishSolve` on the victim address, executing `want.transferFrom(solver, users[i], assetsToUser)`. This mechanism exploited the ERC-20 approval the victim had previously granted to steal funds.
The attack highlights a vulnerability where the solver role was not properly restricted to the caller. The incident resulted in the direct loss of 15.45 ETH from the protocol.
How the market reacted
Whalio's own Binance spot order flow for ETHFI, measured when this story was written up on 11 September 2026. Not the outlet's figures.
ETHFI is currently trading at $0.6647 on Binance spot markets. Short-term buying pressure is evident, with the 1-hour buy ratio at 57.1% compared to a 51.2% ratio over the last 4 hours. This indicates that aggressive buying is accelerating in the immediate term rather than fading. Volume delta supports this momentum, showing a net inflow of $126,555 in the last hour and $65,658 over four hours. The 24-hour volume delta stands at $1,521,962, with a cumulative CVD of $350,772. This flow data suggests that buyers are actively absorbing sell-side liquidity across the day.
The latest daily buy ratio of 47.2% sits at the 18th percentile of the last 324 days, against a median of 49.5% - weaker buying than most days.
Was that an ordinary day?
The same Binance spot measurements for ETHFI, averaged over the days leading up to the story.
Over the preceding week, the 7-day average buy ratio was 50.0%, making today's 24-hour ratio of 53.7% an unusual shift toward buyers. Trading volume has surged to 5.03 times the weekly average, indicating significantly heightened activity. The coin has seen a price change of +12.6% over the last 8 days, driven by net buying on 5 of the 7 days. This volume delta of $1,693,516 over the week underscores a sustained period of accumulation. Today's activity represents a continuation of this broader weekly trend rather than an isolated event.