Optus scammer pleads guilty to blackmail

A NSW teenager has pleaded guilty to trying to blackmail Optus customers affected by its September data breach.

Dennis Su, 19, texted 93 Optus customers, demanding they transfer $2000 to a CBA bank account "or face their personal information being used for financial crimes".

Su downloaded the personal details from a website that shared breached data, telling police he was having a difficult time being unemployed and wanted to make some "quick money".

No one ever transferred the money, however one person responded with an emoji, according to the agreed facts of the case.

Su then returned to the data-sharing website and gathered more information about the victim to "prove his credibility".

He responded by saying: "The police have your details, and I have nothing you can gain so good luck".

The teenager then deleted all the messages before being arrested on October 6.

Su pleaded guilty to two counts of using equipment connected to a network to commit a serious offence on Tuesday in Downing Centre Local Court.

His lawyers submitted a letter of apology from the teenager as well as character references from two counsellors he's been seeing since the charges were laid.

Su is not alleged to be involved in the Optus hack which exposed the personal details of 10 million Optus customers in a data breach in September, including customers' passport, licence and Medicare numbers.

The Australian Federal Police is running two inquiries into who obtained and attempted to sell the Optus data, and protections for more than 10,000 customers who had their records posted online.

The consumer watchdog has been flooded with Optus-related scam complaints following the data breach.

Su is out on bail and is set to face a sentencing hearing on February 7.