CVE-2024-29999 is a vulnerability identified in the Windows Mobile Broadband Driver component of Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The underlying issue is an integer overflow or wraparound (CWE-190), which occurs when an arithmetic operation attempts to create a numeric value that is outside the range that can be represented with a given number of bits, causing the value to wrap around unexpectedly. This vulnerability can be exploited remotely without requiring user interaction or privileges, as indicated by the CVSS vector (AV:P/AC:L/PR:N/UI:N). The flaw allows an attacker with network access to the affected driver to execute arbitrary code on the target system, potentially leading to full compromise of confidentiality, integrity, and availability of the affected device. The vulnerability is rated with a CVSS 3.1 base score of 6.8, categorized as medium severity. No known exploits have been reported in the wild as of the publication date (May 14, 2024), and no patches have been linked yet. The vulnerability affects a legacy version of Windows 10 (1809), which is no longer the latest but may still be in use in certain environments. The integer overflow in the Mobile Broadband Driver could be triggered by specially crafted network packets or data sent to the driver, leading to remote code execution without authentication or user interaction. This makes it a significant risk for systems that still operate on this version and have the vulnerable driver enabled and exposed to network access.

For European organizations, the impact of this vulnerability can be substantial, particularly for those still running Windows 10 Version 1809 in production environments. The ability for remote code execution without authentication or user interaction means attackers could potentially gain full control over affected systems remotely, leading to data breaches, disruption of services, or use of compromised machines as footholds for lateral movement within networks. Critical infrastructure, government agencies, and enterprises relying on legacy Windows 10 systems with Mobile Broadband capabilities are at risk. The confidentiality of sensitive data could be compromised, integrity of systems altered, and availability disrupted through denial-of-service or destructive payloads. Since the vulnerability affects a network-facing driver, it could be exploited over mobile broadband connections or other network interfaces, increasing the attack surface. Although no exploits are known in the wild yet, the medium severity score and ease of exploitation without privileges or user interaction suggest that threat actors may develop exploits soon, especially targeting unpatched legacy systems common in industrial, healthcare, and public sectors across Europe.

1. Immediate mitigation involves upgrading affected systems to a supported and patched version of Windows 10 or later where this vulnerability is resolved. Organizations should prioritize migrating away from Windows 10 Version 1809, which is out of mainstream support. 2. If upgrading is not immediately feasible, disable or restrict the Mobile Broadband Driver functionality where possible, especially on systems that do not require mobile broadband connectivity. 3. Implement network-level controls such as firewall rules to limit exposure of systems with Mobile Broadband interfaces to untrusted networks, reducing the attack surface. 4. Monitor network traffic for anomalous or malformed packets targeting mobile broadband interfaces that could indicate exploitation attempts. 5. Employ endpoint detection and response (EDR) solutions capable of detecting suspicious activity related to driver exploitation or remote code execution attempts. 6. Maintain strict asset inventory to identify all systems running Windows 10 Version 1809 and prioritize remediation efforts accordingly. 7. Stay updated with Microsoft security advisories for the release of patches or workarounds and apply them promptly once available.