ChainBleedv0.1 · open intel
← back to feed·ETHINFRASTRUCTURE2020-08-04 · 5y ago
Incident · CHAINSEC

Opyn

Exploit
Estimated loss
$370.0K
VERDICT —OUT OF SCOPE
Root cause is infrastructure (DNS / cloud / database / third-party API) compromise, not on-chain contract logic. Pre-deployment source review would not surface this; coverage lives in cloud-security + supply-chain audit, separate discipline.
▰ METHOD
INFRASTRUCTURE
INFRASTRUCTURE
Root cause

Root-cause analysis not yet published. The incident description below contains all currently available signal — review the attack transaction directly for definitive forensics.

▰ PROOF OF CONCEPT
DEFIHACKLABS
src/test/2020-08/Opyn_exp.sol
view forked test on github ↗

Reproducible Foundry test fork from SunWeb3Sec/DeFiHackLabs. Clone the repo, run forge test against the file path above, and replay the exploit against a mainnet fork at the historical block. Use for reproduction only — not for live targets.

Forensic narrative

Attackers raided the decentralized finance (DeFi) protocol Opyn yesterday, making off with over 370,000 USDC. Opyn, which deals primarily with options for ETH, was subject to a double-spend attack. Reported loss: $370,000.

Primary source
https://decrypt.co/37671/blatant-bug-led-to-370000-defi-hack-say-experts
Sourced from
chainsec
Technical record
chain
ethereum
protocol
Opyn
bug_class
infrastructure
date_occurred
2020-08-04
loss_usd
$370,000
source_id
cs:opyn::2020-08-04
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