Big four accounting firm suffers client data exposure


In September 2017, one of the big four global accountancy firms and also one of the biggest names in cyber security consulting (Gartner’s security consultancy of the year in 2016) disclosed that they had been the victim of a cyber attack which compromised a server that contained the emails of an estimated 350 clients, including four US government departments, the United Nations and some of the world’s biggest multinationals.

Despite assurances from the company that the hack had only “impacted” six clients and that it was confident it knew where the hackers had been. It said it believed the attack on its systems which began the previous year was over.

The company were criticised for their disclosures with some claiming the incident was more widespread than they acknowledged and that the company cannot be 100% sure what was taken given the nature of the attack (administrator credentials were stolen).

Triggered by the news of the data breach, the information security community relished the opportunity to investigate and expose what they considered to be poor security protocols adopted by Deloitte staff across the globe.

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Courtenay Brammar

Experienced global enterprise risk and governance professional. Previously Vice President at Morgan Stanley, Deloitte Risk Advisory practitioner and PRMIA steering committee member in both London and New York.

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