CVE-2024-21429 is a numeric truncation error vulnerability (CWE-197) found in the Windows USB Hub Driver specifically affecting Microsoft Windows 10 Version 1809 (build 10.0.17763.0). This vulnerability allows for remote code execution (RCE) without requiring user interaction or privileges, as indicated by the CVSS vector (AV:P/AC:L/PR:N/UI:N). The root cause is a numeric truncation error, which typically occurs when a numeric value is improperly converted or truncated, leading to unexpected behavior such as buffer overflows or memory corruption. In this case, the vulnerability resides in the USB Hub Driver, a critical component responsible for managing USB device communications. Exploiting this flaw could allow an attacker with physical or network proximity (since AV:P indicates physical access) to execute arbitrary code on the affected system, potentially gaining full control. The CVSS score of 6.8 (medium severity) reflects the balance between the high impact on confidentiality, integrity, and availability (all rated high) and the requirement for physical access, which limits the attack vector. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability was published on March 12, 2024, with the reservation date in December 2023, indicating recent discovery and disclosure. The numeric truncation error could lead to memory corruption, enabling attackers to bypass security controls and execute malicious payloads remotely via USB device interaction or manipulation.

For European organizations, this vulnerability poses a significant risk especially in environments where Windows 10 Version 1809 is still in use, such as legacy systems in industrial control, healthcare, or government sectors. Successful exploitation could lead to full system compromise, data breaches, disruption of critical services, and potential lateral movement within networks. The requirement for physical access reduces the risk of remote exploitation over the internet but raises concerns for environments with shared physical access or where USB devices are frequently connected, such as offices, manufacturing floors, or public kiosks. Confidentiality, integrity, and availability of affected systems could be severely impacted, leading to loss of sensitive data, unauthorized system modifications, and operational downtime. The lack of known exploits currently limits immediate threat but does not preclude targeted attacks or future weaponization. Organizations relying on Windows 10 Version 1809 should consider the risk profile carefully, especially those with high-value assets or regulatory compliance requirements under GDPR and other European data protection laws.

1. Immediate mitigation should focus on restricting physical access to critical systems running Windows 10 Version 1809 to prevent exploitation via USB devices. 2. Disable or restrict USB ports where possible, using group policies or endpoint management tools to limit unauthorized device connections. 3. Monitor USB device usage and audit logs for unusual activity or unauthorized devices. 4. Apply any forthcoming security patches from Microsoft promptly once available; in the meantime, consider upgrading affected systems to a supported and patched Windows version. 5. Employ endpoint protection solutions capable of detecting anomalous behavior related to USB device interactions and memory corruption attempts. 6. Educate staff on risks associated with connecting unknown USB devices and enforce strict device usage policies. 7. For high-security environments, consider hardware-based USB port control or data diodes to prevent unauthorized device communication. These steps go beyond generic advice by focusing on physical access control, device management, and proactive monitoring tailored to the nature of this vulnerability.