The NZX stock exchange has been attacked for the third day in a row, causing it to crash again.
At 11:10am on Thursday NZX put a halt trade on its cash markets, a spokesperson for the trader told Newshub.
"NZX is continuing to work with its network provider to investigate the source of the issue, following volumetric DDoS (distributed denial of service) attacks from offshore on 25 and 26 August."
A DDoS attack aims to disrupt service by saturating a network with significant volumes of internet traffic.
On Tuesday night, the NZX site was hit by a cyberattack which forced it to halt trading. The site went down again on Wednesday for the same reason.
The repeated attacks signal a "very serious" issue says Professor Dave Parry from AUT's department of computer science.
"The fact that this has happened on a second day indicates a level of sophistication and determination which is relatively rare," he said in a statement on Wednesday.
"Unfortunately, the skills and software to do this are widely available and the disruption of COVID and people working from home all over the world potentially with lower security on their computers means that these attacks are easier than usual."