Critical Azure Bastion Vulnerability: CVE-2025-49752 Allows Privilege Escalation

Overview

A critical vulnerability, identified as CVE-2025-49752, has been discovered in Azure Bastion. This vulnerability allows an attacker to elevate their privileges within the Azure environment. This is a serious issue requiring immediate attention from Azure users.

Technical Details

CVE-2025-49752 stems from an improper access control mechanism within the Azure Bastion service. Specifically, a flaw in the session management or the handling of user permissions allows a malicious actor, under certain conditions, to bypass security checks and gain elevated privileges, potentially leading to unauthorized access to resources within the virtual network. The specific attack vector involves [Redacted due to lack of detail – Placeholder for specific technique discovered in the vulnerability. A real post would detail this.]. Exploitation requires [Redacted due to lack of detail – Placeholder for specific pre-requisites or conditions required for exploitation.].

CVSS Analysis

This vulnerability has been assigned a CVSS score of 10, which is classified as CRITICAL. The high score reflects the potential for complete system compromise. The CVSS vector string is [Redacted – Placeholder for CVSS vector. A real post would include this.]. This score highlights the urgency of patching this vulnerability.

Possible Impact

Successful exploitation of CVE-2025-49752 can have severe consequences, including:

• Unauthorized Access: Attackers can gain unauthorized access to sensitive data and resources within the virtual network.
• Data Breach: Compromised accounts can be used to exfiltrate confidential data.
• Lateral Movement: Elevated privileges can be used to move laterally within the Azure environment and compromise other systems.
• Denial of Service: Attackers can disrupt the availability of Azure Bastion and the resources it protects.
• Complete System Compromise: In a worst-case scenario, an attacker could gain full control of the affected systems.

Mitigation or Patch Steps

Microsoft has released a security update to address CVE-2025-49752. Users of Azure Bastion are strongly advised to apply the update immediately. To update Azure Bastion, follow these steps:

1. Navigate to the Azure portal.
2. Locate your Azure Bastion resource.
3. [Redacted – Placeholder for specific upgrade or patching steps. A real post would detail the specific steps required in the Azure portal.]. Refer to the Microsoft Security Response Center (MSRC) advisory for detailed instructions.
4. Verify the updated version to ensure the patch has been successfully applied.

Workarounds: While patching is the preferred solution, if immediate patching is not possible, consider implementing network segmentation and limiting access to Azure Bastion to only authorized users. Monitor Azure Bastion logs for suspicious activity.