Press Release

Tenable Research Discovers High Severity Vulnerability in Microsoft Azure

Vulnerability affects more than 10 Azure services and will not be patched

Tenable — the Exposure Management company, has disclosed that its Tenable Cloud Research Team has discovered a high severity vulnerability in Azure that affects more than 10 Azure services, including Azure Application Insights, Azure DevOps, Azure Machine Learning, Azure API Management and Azure Logic Apps. Microsoft does not plan to issue a patch for this vulnerability. Instead it has created centralised documentation to inform customers about usage patterns for service tags.

The vulnerability allows a malicious attacker to bypass firewall rules based on Azure Service Tags by forging requests from trusted services. A threat actor could exploit Service Tags that have been allowed through a user’s firewall if there are no additional validation controls. By exploiting this vulnerability, an attacker could gain access to an organisation’s Azure service and other internal and private Azure services.

“This vulnerability enables an attacker to control server-side forge requests, thus impersonating trusted Azure services,” explains Liv Matan, senior research engineer, Tenable. “We highly recommend customers take immediate action. By ensuring that strong network authentication is maintained, users can defend themselves with an additional and crucial layer of security.”

Azure customers whose firewall rules rely on Azure Service Tags for security are at risk from this vulnerability and should take immediate action to mitigate the issue to ensure they are protected by robust layers of authentication and authorisation.

More information, including the team’s technical findings and proof of concept, has been published on the Tenable blog and in the technical advisory.

About Tenable

Tenable®️ is the Exposure Management company. Approximately 44,000 organizations around the globe rely on Tenable to understand and reduce cyber risk. As the creator of Nessus®️, Tenable extended its expertise in vulnerabilities to deliver the world’s first platform to see and secure any digital asset on any computing platform. Tenable customers include approximately 65 percent of the Fortune 500, approximately 50 percent of the Global 2000, and large government agencies. Learn more at