CVE-2024-38056 is a medium-severity vulnerability classified under CWE-125 (Out-of-bounds Read) affecting the Microsoft Windows Codecs Library in Windows 10 Version 1809 (build 10.0.17763.0). The flaw arises from improper bounds checking during processing of certain codec data, allowing an attacker with local privileges to read memory outside the intended buffer boundaries. This can lead to disclosure of sensitive information residing in adjacent memory areas, potentially exposing confidential data. The vulnerability requires the attacker to have low-level privileges on the affected system but does not require user interaction, increasing the risk in environments where untrusted local users exist. The CVSS vector (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N) indicates local attack vector, low complexity, low privileges, no user interaction, unchanged scope, and high confidentiality impact without affecting integrity or availability. No known exploits have been reported in the wild, and Microsoft has not yet released a patch, though the vulnerability has been publicly disclosed. This vulnerability specifically targets Windows 10 Version 1809, which is an older, out-of-support or limited-support version, meaning many organizations may still be running it due to legacy application dependencies or delayed upgrade cycles. The Codecs Library is a core component used for media processing, so the vulnerability could be triggered by processing specially crafted media files or data streams. The out-of-bounds read does not allow code execution but can leak sensitive memory contents, which could be leveraged for further attacks or information gathering.

For European organizations, the primary impact is the potential exposure of sensitive information stored in memory on Windows 10 Version 1809 systems. This could include credentials, cryptographic keys, or other confidential data, which may facilitate subsequent attacks such as privilege escalation or lateral movement. Organizations in sectors with strict data protection requirements (e.g., finance, healthcare, government) could face compliance risks if sensitive data is leaked. Since exploitation requires local access with low privileges, the threat is more significant in environments where multiple users share systems or where attackers can gain limited access through other means (e.g., phishing, insider threats). The lack of impact on system integrity or availability reduces the risk of service disruption but does not diminish the confidentiality concerns. The absence of known exploits in the wild provides a window for proactive mitigation. However, the continued use of legacy Windows 10 1809 systems in many European enterprises and public sector organizations increases the potential attack surface. The vulnerability could also affect embedded or specialized devices running this Windows version, which are common in industrial and critical infrastructure sectors.

1. Restrict local access to Windows 10 Version 1809 systems by enforcing strict access controls and user permissions, minimizing the number of users with local login capabilities. 2. Monitor and audit local user activities to detect suspicious attempts to access or process media files that could trigger the vulnerability. 3. Apply any Microsoft patches or security updates as soon as they become available for this vulnerability. 4. Where possible, upgrade affected systems to a supported and fully patched Windows version to eliminate exposure to this and other legacy vulnerabilities. 5. Use application whitelisting and endpoint protection solutions to prevent execution or processing of untrusted or suspicious media files. 6. Educate users about the risks of opening untrusted media content, especially on legacy systems. 7. For critical environments, consider network segmentation to isolate legacy Windows 10 1809 systems from sensitive networks and data. 8. Employ memory protection and exploit mitigation technologies available in Windows Defender Exploit Guard or third-party solutions to reduce the risk of memory disclosure. 9. Maintain an inventory of all systems running Windows 10 Version 1809 to prioritize remediation efforts effectively.