CVE-2025-59291
📋 TL;DR
This vulnerability in Azure Container Instances allows authorized attackers to manipulate file paths, potentially leading to local privilege escalation. It affects users of Azure Container Instances with specific configurations that allow external control of file names or paths.
💻 Affected Systems
- Azure Container Instances
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
An attacker gains full administrative control over the container instance, potentially accessing sensitive data, modifying configurations, or pivoting to other resources.
Likely Case
Authorized users with limited privileges can elevate their access within the container to perform unauthorized actions or access restricted data.
If Mitigated
With proper access controls and monitoring, impact is limited to isolated container instances without affecting broader Azure resources.
🎯 Exploit Status
Requires authorized access to the container instance; exploitation involves manipulating file path inputs.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Microsoft Azure updates for Container Instances
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-59291
Restart Required: Yes
Instructions:
1. Review Microsoft Security Advisory. 2. Update Azure Container Instances to latest version. 3. Restart affected containers. 4. Verify no unauthorized changes occurred.
🔧 Temporary Workarounds
Restrict Container Permissions
linuxLimit container capabilities and run with minimal privileges to reduce impact of potential escalation.
az container create --name mycontainer --image myimage --cpu 1 --memory 1.5 --restart-policy Never --command-line "tail -f /dev/null" --os-type Linux --location eastus --assign-identity --role "AcrPull" --scope /subscriptions/{subscription-id}/resourceGroups/{resource-group}/providers/Microsoft.ContainerRegistry/registries/{registry-name}
🧯 If You Can't Patch
- Implement strict input validation for all file path inputs in container applications.
- Use Azure Policy to enforce container security best practices and monitor for suspicious activities.
🔍 How to Verify
Check if Vulnerable:
Review container configurations for external file path control and check Azure Security Center for vulnerabilities.Check Version:
az container show --name mycontainer --resource-group myResourceGroup --query "instanceView.currentState.detailStatus"Verify Fix Applied:
Confirm container instances are updated to latest Azure platform version and validate no path manipulation vulnerabilities exist.📡 Detection & Monitoring
Log Indicators:
- Unusual file path access patterns in container logs
- Privilege escalation attempts in Azure Activity Logs
Network Indicators:
- Unexpected outbound connections from containers after path manipulation
SIEM Query:
AzureActivity | where OperationNameValue contains "Microsoft.ContainerInstance" and ActivityStatusValue contains "Failed"