The NZX has been hit by a third consecutive cyber attack, blocking access to its website and public announcement system, and will not resume trading until tomorrow.
In an email seen by BusinessDesk, the NZX’s trading & clearing systems incidents team said the exchange had decided to not restart trading.
The NZX dairy derivatives and equity derivatives markets, which had been trading, closed at 4pm.
The exchange has been targeted by a string of distributed denial of service attacks since Tuesday which have now disrupted trading for three days in a row.
The stock market operator said it halted trading in the cash markets at 11.10am due to a connectivity issue.
"NZX is continuing to work with its network provider to investigate the source of the issue, following volumetric DDoS attacks from offshore on 25 and 26 August," it said.
While the exchange’s internal systems are not being reached by the attacks, the loss of access to the public announcements creates a risk of information asymmetry and requires trading to be halted.
Director of Cert NZ, Rob Pope said yesterday that the attacks were an example of the increasingly sophisticated cyber crime targeting New Zealand.
Before the disruption, the S&P/NZX 50 was trading at 12,053.43, a hairsbreadth below its February all-time high of 12,073.34.
