SBI Crypto Hack
REPORTED ESTIMATE
$21.0M
What happened
SBI Group confirmed on 2 October 2025 that cryptocurrency owned by its overseas mining subsidiary, SBI Crypto, had been transferred out without authorization. Earlier blockchain reporting linked approximately $21 million in suspicious outflows to 24 September. SBI said its domestic exchanges, SBI VC Trade and Bitpoint Japan, used separate asset-management arrangements and were unaffected.
Technical Root Cause
Unauthorized outflows affected company-owned cryptocurrency. SBI's reviewed disclosure did not establish the initial access method, a private-key compromise mechanism or the attacker's identity.
Case & protocol details
Classification
Corporate cryptocurrency custody
Protocol Type
Cryptocurrency mining
Implementation language
C++
Official Website
sbicrypto.com/
How it happened
- Blockchain reporting identified suspicious 24 September outflows involving BTC, ETH, LTC, DOGE and BCH from addresses linked to SBI Crypto.
- The initial public estimate was approximately $21 million. This was an external tracing estimate, not an amount confirmed in SBI's 2 October notice.
- SBI subsequently confirmed the loss of company-owned assets at its overseas mining subsidiary and said the amount and cause were under investigation.
- The company distinguished this incident from its domestic exchange businesses and said it was considering a reorganization of the affected business.
Evidence & learning
Attack pattern
Compare incidents →Sources and on-chain records
- report Report coindesk.com
- report Post-mortem rekt.news
- report CoinDesk: Reported September SBI Crypto outflows coindesk.com
- analysis Web Archive x.com
- analysis Website reference x.com
- analysis SBI Group: Unauthorized asset outflows at SBI Crypto sbigroup.co.jp
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