A NullMeridian record Andromeda Logs

NullMeridianLog

16 Jul 2025

BigONE: Third-Party Attack on Hot-Wallet Asset Transfers

BigONE: on 16 Jul 2025 it detected abnormal asset transfers, suspended deposits/withdrawals/trading, and said a third-party attack hit certain hot-wallet tokens. Private keys said secure; BigONE says it will fully cover losses.

  • Event date
  • Incident typeExchange hot-wallet incident
  • Bug classNot yet published
  • Published

Loss, as sourced

Not stated by BigONE in its 16 Jul announcement. Secondary reporting commonly cites ~$27M; that figure is not taken from BigONE's announcement.

Traceability

Primary sources

  1. 01bigone.zendesk.comBigONE Announcement, 16 Jul 2025 (opens in a new tab)
  2. 02bigone.zendesk.comBigONE Progress Update, 16 Jul 2025 (opens in a new tab)

In brief

Root cause: Per BigONE: third-party attack; affected assets are certain hot-wallet tokens; all wallet private keys remain secure. Detailed vector not in the initial announcement.

Timeline, as sourced: Per BigONE: 16 Jul abnormal transfers detected; deposits, withdrawals and trading suspended; investigation opened; pledge to fully cover losses.

Account, as sourced

Claimed (BigONE) (announcement (opens in a new tab)): will fully cover losses; regular updates promised.

Unknown: quantified loss and full root cause.

Summaries of public sources as of the published date; except where marked (on-chain), not independently verified by NullMeridian. Figures are the sources’ own and are attributed; where sources disagree, each is given. Sources may since have changed. Not legal, financial or investment advice.

Permalinkhttps://andromeda.observer/e/bigone-hot-wallet-2025