Hack history / 2021 / Hack or exploit
Gamma
Hack or exploit on Dec 21, 2021 · Reentrancy
ONE SOURCE · 1 SOURCE
Lost
$8.2M
dollars at the time
Returned
none listed
as the sources state it
Rank
#343
among thefts by dollars lost
What happened
Visor Finance's staking contract was exploited via reentrancy in the delegateTransferERC20 interface. Attackers recursively called the withdrawal function before state updates were completed, stealing 8,812,958 VISR tokens (~$8.2M).
Details
- Date
- Dec 21, 2021
- Kind
- Hack or exploit
- Method
- Reentrancy
- How in
- Smart contract bug
- Target
- DeFi protocol
- Chains
- Ethereum
Reported by
Related incidents
Gamma 2024 · Hack or exploit · $6.2M
Zircon Gamma 2023 · Hack or exploit · $350K
Gamma 2021 · Hack or exploit · $4.5M
Grim Finance 2021 · Hack or exploit · $30M
CREAM Lending 2021 · Hack or exploit · $18.8M
Zircon Gamma 2023 · Hack or exploit · $350K
Gamma 2021 · Hack or exploit · $4.5M
Grim Finance 2021 · Hack or exploit · $30M
CREAM Lending 2021 · Hack or exploit · $18.8M
Cite this page
SwanBluechip, "Gamma hack, Dec 21, 2021: $8.2M lost", Crypto hack history, https://swan-hack-tracker.pages.dev/history/i/ht368b6b7d37/ (data as of 2026-10-31).