CVE-2024-30099 is a high-severity vulnerability identified in Microsoft Windows 10 Version 1809 (build 10.0.17763.0). It is classified as a Time-of-check Time-of-use (TOCTOU) race condition, specifically CWE-367. This type of vulnerability arises when a system checks a condition (such as permissions or resource state) and then uses the resource based on that check, but the state changes between the check and the use, allowing an attacker to exploit the timing gap. In this case, the flaw exists within the Windows kernel, which is the core component responsible for managing system resources and enforcing security boundaries. The vulnerability allows an attacker with low privileges (PR:L) and local access (AV:L) to elevate their privileges to higher levels, potentially SYSTEM or kernel-level privileges, without requiring user interaction (UI:N). The attack complexity is high (AC:H), meaning exploitation requires specific conditions or timing, but the impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H). The scope is unchanged (S:U), indicating the vulnerability affects only the vulnerable component and does not extend beyond it. Although no known exploits are currently observed in the wild, the vulnerability is publicly disclosed and rated with a CVSS 3.1 score of 7.0, indicating a significant risk. The lack of available patches at the time of publication increases the urgency for mitigation. This vulnerability could be leveraged by attackers to bypass security controls, execute arbitrary code with elevated privileges, and compromise system integrity and confidentiality.

For European organizations, the impact of CVE-2024-30099 is substantial, especially for those still operating legacy or unpatched Windows 10 Version 1809 systems. Elevation of privilege vulnerabilities in the kernel can lead to full system compromise, allowing attackers to install persistent malware, exfiltrate sensitive data, or disrupt critical services. Sectors such as finance, healthcare, government, and critical infrastructure, which often rely on Windows environments, could face severe operational and reputational damage. The high impact on confidentiality, integrity, and availability means that sensitive personal data protected under GDPR could be exposed, leading to regulatory penalties and loss of customer trust. Additionally, the complexity of exploitation and requirement for local access suggest that insider threats or attackers who have already gained limited footholds could escalate privileges rapidly. The absence of known exploits in the wild currently provides a window for proactive defense, but organizations must act swiftly to prevent potential future attacks.

1. Immediate prioritization of patching: Although no patches were linked at the time of disclosure, organizations should monitor Microsoft’s official channels for updates and apply security patches as soon as they become available. 2. Upgrade or migrate systems: Given that Windows 10 Version 1809 is an older release, organizations should plan to upgrade to supported, fully patched Windows versions to reduce exposure. 3. Implement strict access controls: Limit local administrative privileges and restrict user accounts to the minimum necessary permissions to reduce the risk of privilege escalation. 4. Employ endpoint detection and response (EDR) tools: Use advanced monitoring to detect unusual kernel-level activity or privilege escalation attempts. 5. Harden system configurations: Disable unnecessary services and features that could be leveraged to gain local access. 6. Conduct regular security audits and penetration testing focusing on privilege escalation vectors. 7. Educate users and administrators about the risks of local exploits and enforce strong physical and network access controls to prevent unauthorized local access.