CVE-2024-35254 is a vulnerability identified in Microsoft Azure Monitor Agent version 1.0.0, classified under CWE-59: Improper Link Resolution Before File Access ('Link Following'). This flaw arises when the agent improperly resolves symbolic links or junction points before accessing files, potentially allowing an attacker with limited privileges (local authenticated user) to manipulate file paths. By exploiting this, an attacker can perform an elevation of privilege attack, gaining higher-level access than intended. The vulnerability has a CVSS 3.1 base score of 7.1, indicating high severity, with attack vector being local (AV:L), low attack complexity (AC:L), requiring low privileges (PR:L), and no user interaction (UI:N). The impact affects integrity and availability, meaning attackers could alter monitoring data or disrupt monitoring services, which are critical for maintaining cloud infrastructure health and security. Although no active exploits have been reported, the vulnerability's presence in a widely used cloud monitoring agent makes it a significant risk. The vulnerability was published on June 11, 2024, and is currently unpatched, with no official patch links available yet. The improper link resolution could allow attackers to redirect file operations to unauthorized locations, potentially overwriting or corrupting files or executing malicious code with elevated privileges.

For European organizations, the impact of CVE-2024-35254 could be substantial, especially for those heavily reliant on Microsoft Azure cloud services and Azure Monitor for infrastructure monitoring and incident detection. Successful exploitation could lead to unauthorized modification or deletion of monitoring logs and data, undermining the integrity of security and operational insights. This can delay detection of other attacks or system failures, increasing the risk of prolonged outages or data breaches. Availability impacts could disrupt monitoring services, impairing the ability to maintain service-level agreements and comply with regulatory requirements such as GDPR, which mandates timely breach detection and response. Organizations in sectors like finance, healthcare, and critical infrastructure, which depend on continuous and reliable monitoring, would be particularly vulnerable. The requirement for local access limits remote exploitation but insider threats or compromised low-privilege accounts could leverage this vulnerability to escalate privileges and cause significant damage.

Immediate mitigation steps include restricting local access to systems running Azure Monitor Agent version 1.0.0 to trusted administrators only, minimizing the attack surface. Implement strict file system permissions to prevent unauthorized users from creating or manipulating symbolic links or junction points in directories accessed by the agent. Monitor system logs for unusual file access patterns or privilege escalations. Employ application whitelisting and endpoint detection and response (EDR) tools to detect and block suspicious activities related to file system manipulation. Organizations should prioritize testing and deploying official patches from Microsoft once released. Until patches are available, consider isolating or limiting the use of the vulnerable agent on critical systems, or temporarily disabling non-essential monitoring features that rely on the agent. Regularly update and audit cloud agent configurations and access controls to ensure adherence to the principle of least privilege.