Telstra has said that an error in its website's search function led to 18 customers' personal information including name, business name, address, phone number, and email address being breached.
According to Telstra, it accidentally made these details available to three customers via its Your Telstra Tools online help service for small business and enterprise customers.
"We take the privacy and security of our customers extremely seriously, so we took the immediate step to disable Your Telstra Tools while our IT Security team investigated," a blog post by head of Sales and Service Michael Ackland said.
"The team identified emails from Telstra to 18 customers about planned network interruptions had been made available to three customers who performed a specific search on the site. The issue was caused by an error in the system's search function."
Ackland added that Telstra has begun notifying and apologising to the affected customers, and will "remain vigilant to keep our data and systems safe and secure".
The blog post followed reports by Nine News on Friday that one customer had gained access to a Telstra database with the details of 66,500 customers' names, addresses, phone numbers, and email addresses by searching the term "email" on the telco's website after logging in to his account.
This included the details of a Department of Defence employee, Nine reported.
Telstra had earlier on Monday announced that it will be axing CFO Warwick Bray and group executive of Technology, Innovation and Strategy Stephen Elop, along with group general counsel Will Irving and group executive of Media Joe Pollard.
In total, 8,000 jobs will be axed as part of the Telstra2022 restructure announced by CEO Andy Penn last month, with the Communications Workers Union (CWU) claiming that the telco is offering a "disgraceful and insulting pay offer" for those being made redundant.
"1.5 percent each year for Workstream employees, along with a 1.5 percent pay pool offer for Job Family employees, meaning some Job Family employees may not even receive 1.5 percent," CWU reported on Friday.
"This, along with the removal of Job Family bonuses from the EA, gives Job Family employees no guaranteed individual pay outcome whatsoever -- management are in full control.
"Whilst we have locked in your conditions, your union cannot support Andy's disgraceful pay offer and Telstra is refusing to hold any further discussions on the matter."
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