CVE-2024-21638: Authentication Bypass in Azure IPAM

The impact of CVE-2024-21638 is severe due to the potential for privilege escalation and data exfiltration. An attacker exploiting this vulnerability could impersonate an administrator within Azure IPAM, gaining access to IP address management data. More concerningly, the vulnerability could be leveraged to access underlying Azure resources, potentially leading to data breaches, service disruption, and unauthorized modifications to the Azure environment. While the service principal used by Azure IPAM is designed with limited permissions (Reader role at the root Management Group), the authentication bypass effectively circumvents these controls, allowing an attacker to act as a privileged user.

1. Reserved2023-12-29
2. Published2024-01-10
3. Modified2025-06-03
4. EPSS updated2026-04-02

The primary mitigation for CVE-2024-21638 is to immediately upgrade Azure IPAM to version 3.0.0 or later. If upgrading is not immediately feasible, consider implementing stricter network segmentation to limit access to the Azure IPAM instance. Review and audit existing Azure IPAM user permissions to ensure least privilege principles are enforced. Monitor Azure IPAM logs for any suspicious activity, particularly authentication attempts from unexpected sources. While a WAF or proxy cannot directly prevent this authentication bypass, they can be configured to monitor for unusual traffic patterns associated with potential exploitation attempts.