Mobile operator EE has had to fend off an increased number of cyber attacks since TalkTalk revealed it had 15,000 customers financial details stolen.
EE chief executive Olaf Swantee told City A.M.:
Since the TalkTalk breach we have seen heightened activity from criminals and people who want to access our system.
“We have successfully prevented these attacks, but we are reviewing what we can do better to protect customers data,” Swantee added.
Digital security at companies that store customer's financial information have been under increased scrutiny since the attack on TalkTalk last month.
TalkTalk has said the loss of 157,000 of its customers' personal details, including 15,000 people’s financial details, could cost the company up to £35m.
EE is set to be acquired by TalkTalk rival BT Group for £12.5bn and deal has been provisionally cleared by the Competition and Markets Authority.
The cost of hack attacks and data breaches was found to have doubled this year, according to a recent government report.
The initial costs of a major security breach at a large organisation rose to an average £1.46m, jumping from £600,000 in 2014, due to disruption, lost sales, recovery of assets, fines and compensation.
The costs to smaller firms also rocketed to to £310,000 from £115,000 last year.
Swantee said: “We come under attack everyday, and these attacks are not going to stop. On the contrary, I think we will more of this kind of attack.”