Binance removes API keys linked to SignalPlus after reported security issue

SignalPlus is a Hong Kong-based options trading terminal valued at roughly $500 million, giving institutional traders API-based access to exchanges including Binance and Deribit. The incident surfaces a week after Binance itself disclosed a $6.4 billion hack attributed to North Korean actors, keeping exchange security under scrutiny. Third-party trading tools routinely hold API keys with permissions to view and sometimes execute orders on connected accounts, making them a recurring target distinct from the exchanges' own infrastructure.

SignalPlus users on Binance lost automated access until they logged in directly, checked every open position and order, and waited for an official all-clear before reconnecting. Changpeng Zhao went further, urging traders using SignalPlus on any exchange, not only Binance, to pull those API keys as a precaution. Deribit customers faced the same disruption. Binance account holders with no SignalPlus exposure saw no change, since the exchange said its core systems and funds stayed untouched.

The breach did not exploit a smart contract or a cold wallet; it began with a fake Microsoft Teams calendar invitation that reached an engineer's computer, a reminder that social engineering remains the cheaper route into crypto infrastructure than any protocol flaw. It also exposes how much institutional trading depends on third-party terminals holding live API keys across multiple venues, a single point of failure that no individual exchange's own security budget can fully cover.

SignalPlus has pledged to reimburse the under-$82,000 in losses in full, a commitment worth tracking once its internal review closes. Also worth watching: whether Binance and Deribit restore API access on a blanket basis or require individual reconnection approval, and whether either exchange publishes a postmortem naming the specific vulnerability the fake Teams invite exploited, which would clarify how exposed other third-party trading terminals remain.