Hackers involved in Home Depot attack have reportedly used earlier unseen malicious software programme called ‘Mozart’, warned a report from the US Department Homeland Security.

Drawing on data from the Secret Service involved in investigating the breach, the report confirmed that the malware had been customised for the systems deployed by the American DIY chain.

It claimed to be designed to steal credit card numbers and work same as a computer code used in other high profile breaches, but in order to avoid detection through security aparatus, it uses different ways to carry out its mission at each turn.

Citing the report, the Wall Street Journal noted that the malware used file names that merged genuine filenames and were unique to technology deployed by Home Depot.

During the event of breach, Home Depot was upgrading to a fresh version of Symantec antivirus software.

Home Depot spokesman noted that the DIY chain has ‘extensive IT security measures and we make substantial investments to meet evolving threats.’

The breach in the DIY chain’s point-of-payment systems, which came to light on 2 September, has reportedly compromised 56 million credit and debit cards, in what is claimed to be the largest ever credit card disclosure.

Earlier, another report from security blogger Brian Krebs noted that the five-month Home Depot breach involved the same malware as used to attack the retailer Target, called BlackPOS,Kaptoxa.