CVE-2024-38055 is a vulnerability identified in the Microsoft Windows Codecs Library specifically affecting Windows 10 Version 1809 (build 10.0.17763.0). The root cause is improper input validation (CWE-20), which can lead to information disclosure. This means that when the codecs library processes certain inputs, it fails to properly validate them, potentially allowing an attacker with local access and low privileges to extract sensitive information from the system. The vulnerability does not require user interaction, which lowers the barrier for exploitation once local access is obtained. The CVSS 3.1 base score is 5.5, indicating a medium severity level, with the vector showing local attack vector (AV:L), low attack complexity (AC:L), low privileges required (PR:L), no user interaction (UI:N), unchanged scope (S:U), and high impact on confidentiality (C:H) but no impact on integrity (I:N) or availability (A:N). No known exploits have been reported in the wild yet, and no official patch links are provided at this time, though the vulnerability is publicly disclosed and tracked by Microsoft and CISA. The flaw could be leveraged by attackers who have already gained some level of access to the system to further extract sensitive data, which could include credentials, configuration details, or other protected information processed by the codecs library. This vulnerability highlights the importance of input validation in multimedia processing components, which are often targeted due to their complex parsing logic.

For European organizations, the primary impact of CVE-2024-38055 is the potential unauthorized disclosure of sensitive information from systems running Windows 10 Version 1809. This could compromise confidentiality of corporate data, intellectual property, or personal data protected under GDPR. Although the vulnerability requires local access with low privileges, it could be exploited by insiders or attackers who have already breached perimeter defenses. Sectors such as finance, healthcare, government, and critical infrastructure that rely on legacy Windows 10 systems may face increased risk. Information disclosure could facilitate further attacks, including privilege escalation or lateral movement within networks. The lack of impact on integrity and availability reduces the risk of system disruption but does not diminish the threat to data confidentiality. Since Windows 10 Version 1809 is an older release, organizations that have not upgraded or patched may be disproportionately affected. The absence of known exploits in the wild provides a window for proactive mitigation before active exploitation occurs.

1. Prioritize upgrading affected systems from Windows 10 Version 1809 to a supported, patched version of Windows 10 or Windows 11 to eliminate exposure. 2. If immediate upgrade is not feasible, apply any available security updates or workarounds from Microsoft as soon as they are released. 3. Restrict local access to vulnerable systems by enforcing strict access controls, limiting administrative privileges, and using network segmentation to reduce the attack surface. 4. Monitor logs and system behavior for unusual local activity that could indicate attempts to exploit the codecs library. 5. Employ endpoint detection and response (EDR) tools to detect suspicious processes or anomalous file access related to multimedia codecs. 6. Educate users and administrators about the risks of running outdated operating systems and the importance of timely patching. 7. Implement application whitelisting and privilege management to prevent unauthorized execution of potentially malicious code that could leverage this vulnerability. 8. Regularly audit systems to identify and remediate legacy Windows 10 1809 installations still in use within the organization.