Microsoft paid Tenable a bug bounty for an Azure flaw it says doesn’t need a fix, just better documentation

Microsoft paid Tenable a bug bounty for an Azure flaw it says doesn't need a fix, just better documentation

June 5, 2024 at 02:48AM

A vulnerability in Microsoft’s Azure cloud allows potential access to other users’ private web resources. The issue stems from Service Tags, potentially allowing cross-tenant attacks. Despite Microsoft’s initial refusal to classify it as a vulnerability, it confirmed the flaw and offered a bug bounty. Subsequently, Microsoft decided to address the issue through improved documentation, emphasizing the importance of a multi-layered security approach.

Based on the meeting notes, the main takeaways are:

1. There is a vulnerability or security weakness in Microsoft’s Azure cloud relating to the use of Service Tags, discovered by the research team at Tenable. This vulnerability potentially allows malicious actors to bypass firewall rules and access other customers’ private web resources. Microsoft initially classified the issue as an “elevation of privilege flaw” with an “important” severity level and paid Tenable a bug bounty.

2. Microsoft initially developed a comprehensive fix for the vulnerability but later decided to address it with only “a comprehensive documentation update.” This decision was based on the belief that the security weakness with Service Tags can best be solved with combined layers of security controls. As a result, instead of a patch, Microsoft has published “improved guidance” for Azure Service Tags in its documentation.

3. Tenable asserts the importance of addressing gaps, whether they are communication gaps or technology gaps, to ensure users’ security. They emphasize the need for customers to implement multiple layers of security to protect valuable resources and data, as relying solely on firewall rules may not be sufficient.

In summary, the vulnerability in Azure’s Service Tags, while initially classified as an “important” issue by Microsoft, was not addressed through a patch but rather through updated documentation and improved guidance. Both Microsoft and Tenable stress the importance of implementing multiple layers of security to protect against potential exploitation of the vulnerability.

Let me know if there is anything else you would like to know.

Full Article