Trading on the stock exchange has resumed after a fourth day of offshore cyber attacks disrupted its operations.
The NZX was back up and running at about 1pm after it delayed trading just minutes before it was due to start this morning as its website, which carries company announcements, was overwhelmed by further attacks.
The company had said earlier that it had strengthened its defences against the attacks with the help of its host company Spark and support from outside consultants including the Government Communications Security Bureau, which was directed by the government to assist.
The NZX website has been the subject of denial of service attacks, which overwhelm the site and make it unavailable. Share trading has been halted because investors could not see up to date company announcements leading to an "uninformed market".
After trading resumed the benchmark NZX-50 index was down about 40 points or 0.4 percent at 12,012, about 100 points shy of a record high.
Inconvenient and uncomfortable
A financial adviser at Hobson Wealth Partners Brad Gordon told Morning Report that the crashes had caused significant inconvenience and come in the middle of the significant company reporting period.
He said having the exchange close abruptly put New Zealand traders at the whim of the overseas market when the market next opens.
"There's a lot of algorithmic trading that happens, say volume weight prices that happens throughout the day, which means those orders will be hanging over a night."
He said clients were getting frustrated.
"There were a number of orders weren't able to be done yesterday, and obviously it just leaves them just a little bit uncomfortable, particularly having to sit on positions overnight that they were expecting to be able to trade."
Gordon said there is a question about why it has been happening to NZX technology infrastructure when it is not happening to other stock exchanges.
The ZDNet technology website said the cyber attacks had occurred around the world over the past two weeks, but the NZX seemed to be among the worst affected.
Among other financial service companies affected have been global payments company PayPal and money transfer companies Braintree and Worldpay.
The article named the groups involved as Armada Collective and Fancy Bear, which it said were sending ransom letters to companies in finance, travel, and e-commerce.
The NZX has made no substantive comment on the attacks or if had received any ransom demands.
Finance Minister Grant Robertson said the GCSB and the national cyber security agencies had been activated to assist the NZX, but declined to give details because of "security considerations."
"We as a government are treating this very seriously, we are aware of the impact it is having and that is why we have directed the GCSB to help the NZX with this situation," he told a Covid-19 briefing.