Hack history / 2020 / Hack or exploit
OKEx
Hack or exploit on Aug 18, 2020 · Forged Proof
SOURCES AGREE ON DATE AND LOSS · 2 SOURCES
Lost
$5.6M
dollars at the time
Returned
none listed
as the sources state it
Rank
#431
among thefts by dollars lost
What happened
Attackers conducted a 51% attack on Ethereum Classic to execute a double-spend against OKEx. They deposited ETC, withdrew it, then reorganized the blockchain to erase the deposit transaction while keeping their funds, resulting in a net $5.6M theft via unconfirmed transaction reversal.
Details
- Date
- Aug 18, 2020
- Kind
- Hack or exploit
- Method
- Forged Proof
- How in
- Bridge and cross-chain
- Target
- Centralized exchange
- Chains
- Ethereum Classic
Reported by
Related incidents
Cite this page
SwanBluechip, "OKEx hack, Aug 18, 2020: $5.6M lost", Crypto hack history, https://swan-hack-tracker.pages.dev/history/i/htf14df50906/ (data as of 2026-10-31).