Ethereum’s Beacon Chain recorded a major slashing event on Sept. 10, with 40 validators penalized for pushing conflicting attestations.

Initial reports pointed to validator nodes tied to StakeFi, Allnodes, and SSV Network. However, further on-chain investigation showed that most affected operators were connected to Ankr.

Beacon Chain reported that one validator was “slashed’ 0.3 ETH, which was worth roughly $1,300 at the time. If similar losses occurred across the group, the cumulative penalty could exceed $52,000.

What went wrong?

Slashing occurs when validators act against consensus rules, often by publishing contradictory attestations.

Preston Vanloon, an Ethereum core developer, explained that such errors usually appear when validator keys are run across multiple environments. In that situation, nodes may see different views of the chain, leading to double-signing and automatic penalties.

He said:

“These validators published conflicting attestations.”

Vanloon further agreed that the issue might have stemmed from the impacted firms’ committing a blunder while migrating a validator.