External control of file name or path in Confidential Azure Container Instances allows an authorized attacker to elevate privileges locally.
What privileges could be gained by an attacker who successfully exploited the vulnerability? The attacker could gain code execution within the confidential ACI sidecar container, escalating from host control to confidential containers. How could an attacker exploit this vulnerability? An attacker could trick the system into mounting a malicious file share to a sensitive location, allowing them to run harmful code. According to the CVSS metric, successful exploitation could lead to a scope change (S:C). What does this mean for this vulnerability? A successful attack allows the container host to execute code in the targeted guest environment. What actions need to be taken to mitigate this vulnerability? To ensure secure and compliant use of Confidential virtual nodes on Azure Container Instances, customers must take the following actions: 1. Update Helm Charts If you are using Confidential virtual nodes, update to Helm chart version 1.3012.25080101 or later. Follow the deployment instructions provided in the https://github.com/microsoft/virtualnodesOnAzureContainerInstances repository. 2. Regenerate CCE Policy If you are using Confidential ACI or Confidential virtual nodes, you must regenerate your Confidential Compute Environment (CCE) policy with a minimum infrastructure fragment SVN of 4. To do this: 1. Update the Azure CLI confcom extension to version 1.2.8 or later: *az extension update --name confcomShow more lines* Alternatively, you can manually set the infrastructure SVN using: *--infrastructure-svn 4* 2. Regenerate the CCE policy using either an ARM template or YAML file, depending on your deployment method. 3. Update any dependent key release policies, such as those using x-ms-sevsnpvm-hostdata claim checks in a Managed HSM (mHSM) key release policy. 4. Re-deploy your workload to apply the updated policy and configuration.
Microsoft Offensive Research & Security Engineering, Microsoft Offensive Research & Security Engineering