Bithumb Hack
What happened
Bithumb initially reported approximately ₩35 billion in losses after its June 2018 cyberattack. On 28 June, the exchange revised the provisional damage estimate to about ₩19 billion. Its explanation included assets protected through rapid cold-storage transfers and cooperation with other exchanges and cryptocurrency foundations; the reduction should not all be described as stolen funds returned by the attacker.
Unauthorized exchange asset outflows were confirmed, but the reviewed Bithumb notice does not identify the initial intrusion route. A particular key leak or software vulnerability is not established by that source.
Case & protocol details
How it happened
- Bithumb announced an initial damage estimate of approximately ₩35 billion on 20 June.
- The exchange moved cryptocurrency from hot wallets into cold storage and worked with other exchanges and foundations to limit the damage.
- On 28 June, it revised the provisional estimate to approximately ₩19 billion, explaining that some assets initially feared lost had been preserved.
- Deposits remained suspended while Bithumb replaced systems and continued recovery work. It also announced compensation for the withdrawal-service disruption.
Evidence & learning
Attack pattern
Compare incidents →Sources and on-chain records
Build your security review skills
Work through hands-on labs covering real exploit mechanics, review techniques, and defensive patterns.
