More website wobbles for Westpac

Westpac customers were unable to gain access to the bank's website for part of Monday and throughout most of yesterday as the bank worked to resolve what is described as a system upgrade gone wrong.

The bank said internet banking services were maintained but the bank's home page had a "threshold capacity issue". Retail and business customers who rang the online banking assistance line were directed to separate online personal and business banking URLs and were able to do their banking.

Westpac group executive for consumer financial services, Mike Pratt, said an upgrade installed over the weekend had tested successfully but had not handled the traffic on Monday.

Pratt said the bank's IT staff were working hard to fix the problem. He said it was not a security issue.

Westpac established an alternative, and slimmed down, home page overnight that provided links to the main transaction pages within the bank's website. Most links within those transaction pages (to other content) were not working as of early this morning. Nor were some bookmarked URLs for subsidiary pages.

IT industry sources speculated, rather wildly, given Westpac's account, that the bank was the victim of a botnet attack - in which tens of thousands or even more malware-infected PCs mount a denial of service attack on the bank's internet service provider.

The bank's online banking system last crashed on August 23, leaving customers without online banking services for about an hour.

On that occasion a spokesperson said the crash was the result of a hardware failure and that everything had been restored after the outage.

In July the bank's security system was breached and 1400 Virgin credit card holders had their account details exposed (Westpac is Virgin's credit card partner).

In June the bank's internet system crashed for three hours as a result of a denial of service attack.

Also in June the bank suffered an online and ATM outage that it blamed on human error.

Jeff McGeorge, a director of the online security developer Markets-Alert, said outages of this kind were becoming increasingly common, both here and overseas.

McGeorge said: "In many cases there is no hard evidence but in other cases we do know that these outages are linked to various attacks."

Ian Povey, the director of Cards Consult, agreed that banks were suffering more frequent online system crashes.