The Telstra Group Ltd (ASX: TLS) share price is up 0.25% as we head into the lunch hour, having earlier posted gains of more than 0.5%.
Telstra shares closed on Friday at $4.00, with shares currently trading for $4.01 apiece.
While that's not exactly shooting the lights out, it comes as the S&P/ASX 200 Index (ASX: XJO) is down 0.5%.
The Telstra share price gain also comes despite news breaking over the weekend of a significant data breach. This saw the details of 132,000 customers, who had asked to remain unlisted, published in directory assistance and an online version of the White Pages directory.
How was the customer data published?
As reported earlier today, the Telstra data breach was not the result of cybercriminals but rather, according to Telstra, due to a "misalignment of databases".
Commenting on the incident that does not appear to be having a material impact on the Telstra share price today, chief financial officer Michael Ackland said the mistake was uncovered during the company's regular auditing processes.
16,000 of the 132,000 customers had their phone numbers published in an online version of the White Pages directory, with the rest of the customer's information accidentally made available via directory assistance.
Ackland told Today, "We found there were misalignments where customers, who in our databases we believed should have been unlisted, were flagged as listed in the directory assistance database, and those 16,000 customers in the White Pages database."
The customer details from the White Pages were removed immediately after Telstra realised its mistake. The telco is still working to expunge all the customer details from its directory assistance servers.
How has the Telstra share price performed longer-term
As you can see in the chart below, the Telstra share price has dropped 1% over the past 12 months.
Longer-term, the ASX 200 telco is up 9% over five years.