What is Euler Finance (EUL)?
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🟢 The simple version
Plain English — no jargon. Start here.
Euler Finance is a permissionless DeFi lending protocol on Ethereum that lets anyone create a lending market for any ERC-20 token, with the unusual distinction of suffering a $197M flash loan hack in March 2023 — and then recovering all funds through negotiation with the attacker.
The $197M hack and full recovery
In March 2023, Euler Finance was exploited for ~$197 million via a complex flash loan attack targeting a flaw in Euler's donate-to-reserve mechanism. What followed was unprecedented: through on-chain negotiations and communications, the attacker returned all stolen funds within two weeks. Euler's team coordinated with blockchain analytics firms and law enforcement, ultimately leading the hacker to voluntarily return ~$177M in ETH and DAI. Euler v1 was deprecated following the exploit.
EUL token
EUL is Euler's governance token. Euler v2 (launched 2024) introduced the Euler Vault Kit — a modular lending infrastructure allowing customisable isolated lending markets. EUL holders vote on protocol parameters and supported vault configurations. Is EUL legal in India? Yes — 30% tax and 1% TDS apply.
🟡 A bit more detail
For when you want to go a little deeper.
Euler v2 — Euler Vault Kit
Euler v2 rebuilt the protocol from scratch after the 2023 hack, introducing the EVK (Euler Vault Kit): a modular system where anyone can deploy customised isolated lending vaults with configurable parameters. Each vault is independent — risk is contained per vault. This is similar to Silo Finance's per-token isolation model but with more composability via nested vault structures. Euler v2 competes with Morpho Blue and Silo v2 in the isolated lending market.
🟣 The full technical picture
For the technically curious.
Key facts
- Token: EUL (governance)
- March 2023: ~$197M flash loan hack — full recovery via negotiation
- v2: Euler Vault Kit (EVK) modular isolated lending
- vs Morpho/Silo: All isolated lending, different implementations