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Those who purchased, or attempted to purchase, tickets between September 2017 and June 23, 2018, were potentially at risk of fraud.
Tiffany Ryan, Westpac NZ head of financial crime and security, said while the risk of fraud was low, Westpac wanted to take an extra proactive step to protect customers.
"Westpac NZ is in the process of proactively replacing around 30,000 cards, where we have concerns that a customer's card details may have been compromised," Ryan said.
"We have strong fraud controls in place, but we wanted to take an extra proactive step to protect our customers and provide them with peace of mind around this issue."
Westpac customers who receive a new card will have to update any direct debits or similar payments linked to their credit card as soon as the new card has been activated to avoid payment delays.
"The biggest hassle is having to update all your card details … [but] I'd rather be safe than sorry," a Westpac customer told the Herald.
Another customer, Kevin Bligh, who received his replacement card today, said it was a good measure from Westpac despite having to update close to 20 different payments linked to his card.
Ticketmaster UK identified the malicious software on a customer support product hosted by Inbenta Technologies, an external third-party supplier to the online entertainment retail service.
Ticketmaster said less than 5% of their global customer base had been affected by the incident.
A spokeswoman for BNZ said it was not undertaking a large scale reissuance of cards.
"We're confident in the security of our cards, our monitoring and our fraud protection tools. Any fraud reports have been resolved with our customers on a case-by-case basis."
In a statement, ASB said: "We're aware of the issues related to Ticketmaster and we have implemented additional fraud monitoring and security measures to ensure our customers remain protected. We're also continuing to keep the situation under review."
ANZ has also been contacted by the New Zealand Herald.