The New Zealand stock exchange was taken offline for two consecutive days due to a cyber attack.
NZX said it was first hit by a Distributed Denial of Service (DDoS) attack from overseas on Tuesday.
The exchange said the attack “affected NZX network connectivity” and decided to stop trading in the spot markets just before 4pm local time.
Trading briefly paused for the second time on Wednesday, but were resumed before the end of the day.
A DDoS attack is a relatively simple type of cyber attack, in which a wide range of computers all try to connect to an online service at the same time, overwhelming its capacity.
They often use devices compromised by malware that the owners don’t know are part of the attack.
Real traders may have had trouble running their business.
But that doesn’t mean that financial or personal information has been accessed.
NZX said the attack came “from offshore via its network service provider”.
The second attack had disrupted trading for much of the business day – from 11:24 am to 3:00 pm local time, the exchange said.
But despite the hiatus, the trade was at the close of business, near its all-time high.
The New Zealand cybersecurity organization CertNZ issued a warning in November that emails were being sent to financial companies threatening DDoS attacks unless a ransom was paid.
The emails claimed to come from the well-known Russian hacker group Fancy Bear.
But CertNZ said the threat had never been carried out at the time, beyond a 30-minute attack as a scary tactic.