CVE-2024-30089 is a high-severity vulnerability identified in Microsoft Windows 10 Version 1809 (build 10.0.17763.0) affecting the Microsoft Streaming Service. The vulnerability is classified as a Use After Free (CWE-416) flaw, which occurs when a program continues to use a pointer after the memory it points to has been freed. This can lead to memory corruption, potentially allowing an attacker to execute arbitrary code, elevate privileges, or cause a denial of service. Specifically, this vulnerability enables an elevation of privilege attack vector, meaning a low-privileged user or process could exploit the flaw to gain higher privileges on the affected system. The CVSS 3.1 base score is 7.8, indicating a high severity level. The vector string (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) shows that the attack requires local access (AV:L), low attack complexity (AC:L), low privileges (PR:L), no user interaction (UI:N), and impacts confidentiality, integrity, and availability to a high degree (C:H/I:H/A:H). The scope is unchanged (S:U), meaning the vulnerability affects resources within the same security scope. No known exploits are currently reported in the wild, and no patches have been linked yet, suggesting that mitigation might rely on workarounds or awaiting official updates. The vulnerability was reserved in March 2024 and published in June 2024, indicating recent discovery and disclosure. The Microsoft Streaming Service is a component involved in media streaming functionality, and exploitation could allow attackers to compromise system integrity and gain unauthorized control over affected machines.

For European organizations, this vulnerability poses a significant risk, especially for those still operating legacy systems running Windows 10 Version 1809, which is an older release but may remain in use in certain sectors such as manufacturing, healthcare, or government where system upgrades are slower. Successful exploitation could lead to unauthorized privilege escalation, enabling attackers to bypass security controls, access sensitive data, deploy malware, or disrupt critical services. Given the high impact on confidentiality, integrity, and availability, organizations could face data breaches, operational downtime, and compliance violations under regulations like GDPR. The local attack vector means that attackers need some form of access to the machine, which could be achieved via compromised user accounts, insider threats, or lateral movement after initial network intrusion. The lack of user interaction requirement increases the risk of automated exploitation once local access is obtained. Although no exploits are known in the wild yet, the high severity and ease of exploitation suggest that threat actors may develop exploits soon, increasing urgency for mitigation.

European organizations should prioritize identifying and inventorying systems running Windows 10 Version 1809 to assess exposure. Given the absence of an official patch at the time of disclosure, organizations should implement the following specific mitigations: 1) Restrict local access to critical systems by enforcing strict access controls and using endpoint protection solutions to detect suspicious local activities. 2) Employ application whitelisting to prevent unauthorized code execution that could leverage this vulnerability. 3) Use virtualization-based security features and enable Windows Defender Credential Guard and Exploit Protection mitigations where possible to reduce attack surface. 4) Monitor system logs and security events for unusual behavior indicative of privilege escalation attempts. 5) Plan and expedite upgrade paths to later Windows 10 versions or Windows 11, which are not affected by this vulnerability. 6) Segment networks to limit lateral movement opportunities for attackers who gain local access. 7) Educate IT staff and users about the risks of local compromise and enforce strong authentication and endpoint security policies. Once Microsoft releases an official patch, immediate deployment is critical to fully remediate the vulnerability.