New Delhi, Sep 21 (IANS): The malicious outsider attack on food delivery app Zomato that exposed 17 million records was the sixth biggest data breach globally in the first half of 2017, a new report said on Thursday.

According to the "Breach Level Index" released by digital security firm Gemalto, a total of 203.7 million data records were compromised in 18 data breaches in India in the firsh half.

Compared to the last six months of 2016, the number of lost, stolen or compromised records increased by 167 million with 61 per cent of data breach incidents being identity theft.

The continuous attacks on Aadhaar data was another significant data breach related to financial access and identity theft in the country.

Globally, a large portion of the 1.9 billion stolen or compromised data records came from the 22 largest data breaches, each involving more than one million compromised records, the report said.

"IT consultant CGI and Oxford Economics recently issued a study, using data from the Breach Level Index and found that two-thirds of firms breached had their share price negatively impacted," said Jason Hart, Vice President and CTO, Data Protection, Gemalto, in a statement.

"Out of the 65 companies evaluated the breach cost shareholders over $52.40 billion," he added.

A total of 918 data breaches were recorded worldwide, in which more than 500 (59 per cent) had an unaccounted number of compromised data records.

The primary sources of data breaches included malicious outsiders, accounting for 74 per cent of the total -- an increase of 23 per cent from last six months of 2016.

While malicious insider attacks only made up 8 per cent of all breaches, the amount of records compromised was 20 million, up from 500,000 (4,114 per cent increase).

Identity theft was the leading 'type' of data breach, accounting for 74 per cent of the total -- an increase of 49 per cent from the previous semester.