Ransomware ‘Nearly Half Of All Cloud Malware’

Nearly half, or 43.7 percent, of the malicious code found in enterprise cloud applications delivered ransomware in the quarter ended 30 June.

That is according to according to a study by cloud security specialists Netskope, which highlights the growing prevalence of this lucrative form of malware.

It found that the average number of cloud applications used by enterprises rose to 824 for the quarter, up from 777 the previous quarter, with marketing and collaboration tools representing the most popular categories of cloud tools.

Office 365 beats Facebook

Microsoft’s Office 365 beat Facebook as the top cloud application for the first time in Netskope’s rankings, indicating the strong enterprise adoption of Microsoft’s online offerings.

Microsoft’s Outlook.com and OneDrive for Business also beat competition from the likes of Google, according to the rankings based on data from Netskope’s cloud application management tools.

Netskope’s findings underscored the security risks inherent in the cloud model, finding that 55.9 percent of malware-infected files found in cloud applications were shared with internal or external users or shared publicly.

“Ransomware attacks are often initially delivered through phishing and email attacks, but within cloud environments, infected and encrypted files can quickly spread to other users through cloud app sync and share functionality in what is known as the fan-out effect,” the firm stated.

On average 26 pieces of malicious code were found in the cloud applications used by a given organisation, according to the report.

Cloud collaboration on the rise

Netskope found that collaboration tool Slack entered the top 20 list of most popular cloud applications for the first time during the quarter, and warned that the trend makes it easier for sensitive information to be leaked against company policies.

Cloud storage applications were, however, responsible for most violations of data-loss prevention policies, accounting for 76.5 percent of violations, followed by webmail at 18.6 percent.

Technology and IT services firms used the most cloud-based applications, at 855 on average, followed by health care and life sciences companies, with 836.

Marketing tools represented the most numerous cloud tools within enterprises, with 75 being used by companies on average, followed by collaboration applications with an average of 66 per company.

Increasing risks

Netskope warned that in spite of their increasing adoption most cloud applications lack enterprise-grade features including security, audit and certification, service-level agreement, privacy and remediation capabilities.

A study in May found that Office 365 security risks were growing alongside its increasing adoption, finding that nearly three-quarters of enterprise users have at least one account compromised each month.

In June researchers warned that Office 365 users had been targeted by a massive wave of ransomware email messages.

Microsoft said at the time that the attack was not “specific to Office 365” and had been “blocked within hours”.

Research published in August found that more than half of UK firms had been targeted by ransomware attacks in the past year.

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