Abstract: Cyber-security techniques are described for monitoring a cloud environment and identifying potential problems, including malicious threats, to the monitored cloud environment using operational telemetry. Techniques are described for monitoring and collecting data related to reverse or recursive DNS (rDNS) traffic associated with a monitored cloud environment. The recursive DNS traffic includes recursive DNS (rDNS) requests originating from the cloud environment and responses to those requests received from DNS resolvers. This collected data is then analyzed to identify potential threats to the monitored cloud environment. The collected data may be analyzed to identify potential sources of threats and to identify one or more portions of the cloud environment that are the targets of the threats. The analysis may trigger alerts to be generated, actions to be performed (e.g., protective measures), reports to be generated, patterns to be recognized, etc.