Microsoft’s security buying spree continued today with CloudKnox, a startup that built a multicloud permissions management platform to protect cloud infrastructure and identities. The companies did not disclose the terms of the deal.

In a security blog post, Microsoft said CloudKnox will boost Azure Active Directory’s cloud identity and access services and provide customers with granular visibility, continuous monitoring, and automated remediation for hybrid and multicloud permissions. The acquisition also advances Microsoft’s push into zero-trust security, which ensures that only continuously verified users and devices are allowed access to corporate resources and restricts data on a least-privileged basis.

“CloudKnox offers complete visibility into privileged access,” wrote Joy Chik, corporate VP of identity at Microsoft, in a separate blog post. “It helps organizations right-size permissions and consistently enforce least-privilege principles to reduce risk, and it employs continuous analytics to help prevent security breaches and ensure compliance. This strengthens our comprehensive approach to cloud security.”

The technology will allow Microsoft to automate and simply access policy enforcement in one multicloud platform for all human and workload identities, she added.

In addition to Azure Active Directory, Microsoft also plans to integrate CloudKnox with its other cloud security services including 365 Defender, Azure Defender, and Azure Sentinel.

CloudKnox marks Microsoft’s third security startup acquisition in two months. Last week it bought threat intelligence company RiskIQ for a reported $500 million. And in June, Microsoft acquired IoT security startup ReFirm Labs for an undisclosed amount.

Microsoft execs have repeatedly said the company invests more than $1 billion annually on security, and on the company’s earnings call in January Microsoft CEO Satya Nadella said its security business surpassed $10 billion over the past 12 months. This represents more than 40% year-over-year revenue growth, which means Microsoft’s security business grew faster than most of its other products and services.