Visor Finance Hack

Reported loss $505K
Ethereum
Access Control

What happened

Visor Finance's June 2021 incident involved a compromised administrator account. The attacker used an emergency-withdraw capability to take approximately $500,000 in deposits that had not yet entered liquidity-provider positions. Visor said treasury funds reimbursed the affected users.

Technical root cause

A single account could exercise privileged Hypervisor withdrawal functions. Compromising that account exposed unallocated deposits; Visor stated that the incident did not exploit its smart-contract code.

How it happened

  1. The attacker obtained access to an account controlling Hypervisor administrative functions.
  2. They used the emergency-withdraw capability to remove unallocated deposits.
  3. Visor replaced the stolen amounts from its treasury and said it had corrected the use of single-account administrative control.

Protocol details

Classification Yield Aggregator / Access Control
Protocol Type Exploit/Access control
Affected asset / contract VISR
Implementation language Solidity
Protocol links Website @visorfinance

Funds Recovery

100.0%

Recovered

$505K

Net Loss

$0

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