"Secret" Agent Exposes Azure Customers to Unauthorized Code Execution
When customers set up a Linux virtual machine in their cloud, the OMI agent is automatically deployed without their knowledge when they enable certain Azure services. Thanks to the ease of use and abstraction that OMI provides, it is used extensively by Azure services, including Open Management Suite, Azure Insights, Azure Automation. Because Azure provides virtually no public documentation about OMI, most customers have never heard of it and are unaware that this attack surface exists in their environment. We hope to raise awareness of the risks that come with unknown agents running with high privileges in cloud environments, particularly among Azure customers who are currently at risk until they update to the latest version of OMI. We urge the research community to continue to audit OMI and report issues they may find with similar agents. Upgrading OMI happens through the parent Azure service that installed it. We urge customers to verify that their environment is indeed patched and they are running the latest version of OMI. System Center deployments of OMI are at greater risk because the Linux agents have been deprecated. Customers still using System Center with OMI-based Linux may need to manually update the OMI agent.