Cybercriminals have accessed data belonging to T-Mobile by tapping into one of Experian’s servers, it has been revealed.

The wireless network provider said that up to 15 million people have been affected by this major data breach.

Information that has been stolen include names, addresses, birthdays and even encrypted data, including social security numbers and passport details.

Experian, which is one of the world’s largest credit agencies, said that it had made the discovery on 15th September.

It explained that the incident, which it described as “isolated”, is believed to have taken place over “a limited period of time”.

The company was keen to highlight that its vast consumer credit database had not been compromised during the attack.

John Legere, CEO of T-Mobile, commented that he was “incredibly angry” about this data breach.

He was candid in publicly stating that as a result of this unfortunate development, he would be “instituting a thorough review of [T-Mobile’s] relationship with Experian”.

“I take our customer and prospective customer privacy very seriously. This is no small issue for us.”

Mr Legere went on to say: “My top concern and first focus is assisting any and all consumers affected.

“I take our customer and prospective customer privacy very seriously. This is no small issue for us.”

In his statement he clarified that T-Mobile’s system and network had not been exposed, nor were any payment or banking details revealed.

Nevertheless, Experian said that the information accessed by cybercriminals could be used fraudulently.

In response, it is offering all affected T-Mobile customers two years of free credit monitoring and “identity resolution services”.

“Experian is committed to building customers for life and is working tirelessly to improve our security systems and processes,” it went on to say.

“We have taken immediate steps to harden our environment. To ensure our security measures and practices stand up to the high standards to which we hold ourselves.