Security incident · 2026-10-21
Swell
According to the public DefiLlama incident dataset, Swell (Ethereum, Arbitrum, Base, Hyperliquid L1) suffered a security incident on 2026-10-21, with about — reported lost.
| Date | 2026-10-21 |
|---|---|
| Reported loss | — |
| Chain | Ethereum, Arbitrum, Base, Hyperliquid L1 |
| Target type | DeFi Protocol |
| Technique class | Key Compromise |
| Technique | Hot Wallet Key Compromised |
| Bridge incident | No |
| Within 2026 | #299 by loss that year, 0.0% of all reported losses that year |
How this kind of attack works
Private keys or signing rights that controlled the funds were stolen, and the attacker moved the money with valid signatures. On chain it looks like a normal transfer.
Would a pre-payment check have helped
Key compromise is a wallet and key-security matter; screening the counterparty or endpoint does not touch it.