Incident All ledgers
Tether: $31.0m
Tether lost $31.0m on 19 November 2017. Ranked 99th of 1,272 crypto failures, with method, returned funds and comparable incidents.
- Date
- 19 November 2017
- Lost
- $31.0m
- Returned or repaid
- None recorded
- Target
- Token
- Category
- Key Compromise
- Method
- Private Key Compromised
- Chains
- Bitcoin
In November 2017, about $30.95M in USDT was taken from Tether's Treasury wallet and moved to an unauthorized address. Tether froze the tokens as non-redeemable and worked with the Omni Foundation on protocol upgrades to eventually reclaim them.
Against the ledger
- It ranks 99th of the 1,272 incidents with a known loss, and 3rd in 2017.
- It accounts for 17.1% of the $181.0m in known losses in November 2017.
- 153 incidents in the ledger are classified as Key Compromise, for $8.96bn in total. This one is 0.3% of that.
- The ledger records no returned funds.
Closest in size by the same method
| Date | Target | Lost | Type | Method | Returned |
|---|---|---|---|---|---|
| 31 Jan 2026 | Step Finance | $40.0m | DeFi Protocol | Private Key Compromised | — |
| 07 May 2019 | Binance | $40.0m | CEX | Hot Wallet Key Compromised | — |
| 08 Jun 2026 | Humanity | $32.0m | DeFi Protocol | Private Key Compromised | — |
| 01 Nov 2022 | Deribit | $28.0m | CEX | Hot Wallet Key Compromised | — |
| 22 Jul 2026 | AFX Bridge | $24.1m | DeFi Protocol | Validator Key Compromised | — |
All failures in those years · The failures ledger
Amounts are DefiLlama’s estimates and can change as incidents are revalued. Its returned figure can include money a company repaid itself, not only funds recovered from attackers. Source: DefiLlama.
Cite this Bitminer.io, “Tether, failures ledger”, data to 2 November 2026, https://bitminer.io/ledger/incident/tether-2017-11-19/. How this is built