Hack history / 2025 / Hack or exploit

Bunni V2

Hack or exploit on Sep 2, 2025 · Rounding Error

SOURCES AGREE ON DATE AND LOSS · 4 SOURCES

Lost

$8.4M

dollars at the time

Returned

none listed

as the sources state it

Rank

#337

among thefts by dollars lost

What happened

On September 2, 2025, a rounding error in Bunni V2's withdrawal logic allowed attackers to systematically withdraw more tokens than entitled, draining $8.4M across Ethereum ($2.4M) and UniChain ($5.9M).

Details

Date: Sep 2, 2025
Kind: Hack or exploit
Method: Rounding Error
How in: Smart contract bug
Target: DeFi protocol
Chains: Ethereum, Unichain

Reported by

DefiLlama ↗
rekt.news ↗
SlowMist Hacked ↗
Web3 Is Going Great ↗

Related incidents

Balancer V2 2025 · Hack or exploit · $120.5M

Cite this page

SwanBluechip, "Bunni V2 hack, Sep 2, 2025: $8.4M lost", Crypto hack history, https://swan-hack-tracker.pages.dev/history/i/ht2f4d411241/ (data as of 2026-10-31).

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