CVE-2024-29988 is a vulnerability identified in Microsoft Windows 10 Version 1809 (build 10.0.17763.0) that affects the SmartScreen security feature, which is designed to protect users by prompting warnings before executing potentially harmful files or actions. The vulnerability is classified under CWE-693, indicating a failure in protection mechanisms. Specifically, this flaw allows attackers to bypass the SmartScreen prompt, effectively disabling a critical layer of defense that prevents users from inadvertently executing malicious code. The CVSS 3.1 base score of 8.8 reflects the vulnerability's high severity, with an attack vector of network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), but requiring user interaction (UI:R). The scope is unchanged (S:U), but the impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H). This means that successful exploitation could lead to full system compromise, data theft, or disruption of services. Although no exploits have been reported in the wild yet, the vulnerability is publicly known and could be targeted by attackers. The lack of patch links suggests that a fix may not yet be widely available, emphasizing the need for vigilance. The vulnerability's exploitation could be triggered by convincing users to interact with malicious content delivered via email, web, or network shares, making social engineering a likely attack vector. The failure of the SmartScreen prompt undermines user trust and security posture, increasing the risk of malware infections and unauthorized system modifications.

For European organizations, the impact of CVE-2024-29988 is significant due to the widespread use of Windows 10 Version 1809 in enterprise environments, especially in sectors such as finance, healthcare, manufacturing, and government. The bypass of SmartScreen prompts can lead to successful delivery and execution of malware, ransomware, or advanced persistent threats (APTs), resulting in data breaches, operational disruptions, and financial losses. Confidentiality is at risk as attackers could exfiltrate sensitive data; integrity is compromised through unauthorized changes to system files or configurations; and availability may be affected by destructive payloads or denial-of-service conditions. The requirement for user interaction means that phishing or social engineering campaigns could be effective attack vectors, increasing the risk to organizations with less mature security awareness programs. Additionally, the absence of patches or mitigations at the time of disclosure could prolong exposure. The vulnerability also poses risks to critical infrastructure and public services, where Windows 10 1809 remains in use, potentially impacting national security and public safety.

European organizations should prioritize upgrading affected systems to a newer, supported Windows version where the vulnerability is patched. If immediate upgrading is not feasible, organizations should implement the following mitigations: 1) Enforce strict application whitelisting and execution policies to limit the execution of untrusted files; 2) Enhance email and web filtering to block malicious attachments and URLs that could trigger the vulnerability; 3) Increase user awareness training focused on recognizing phishing and social engineering attempts that could exploit this vulnerability; 4) Utilize endpoint detection and response (EDR) tools to monitor for suspicious behaviors indicative of exploitation attempts; 5) Restrict user privileges to minimize the impact of successful exploitation; 6) Regularly audit and update security policies related to software execution and network access; 7) Monitor security advisories from Microsoft for the release of patches or workarounds and apply them promptly; 8) Consider network segmentation to isolate critical systems running Windows 10 1809 from less secure environments. These targeted actions go beyond generic advice by focusing on compensating controls and proactive detection in the absence of immediate patches.