CVE-2024-49103 is a medium-severity vulnerability identified in Microsoft Windows 10 Version 1809, specifically affecting the Windows Wireless Wide Area Network Service (WwanSvc). The underlying issue is an integer underflow (CWE-191), which occurs when an arithmetic operation causes a value to wrap around below its minimum representable value. This vulnerability can lead to information disclosure, meaning that sensitive data handled by the WwanSvc component could be exposed to unauthorized parties. The vulnerability does not affect system integrity or availability directly but compromises confidentiality. The CVSS 3.1 base score is 4.3, reflecting a scenario where an attacker with low privileges (PR:L) and physical access (AV:P) can exploit the flaw without user interaction (UI:N). The attack complexity is low (AC:L), and the scope remains unchanged (S:U). No known exploits are currently reported in the wild, and no official patches have been linked yet. The vulnerability is specific to Windows 10 Version 1809 (build 10.0.17763.0), an older but still in-use version of Windows 10, particularly in enterprise environments where legacy systems persist. The WwanSvc manages wireless WAN connections, often used in mobile broadband scenarios, which may be more prevalent in mobile or remote workforce contexts. An attacker exploiting this flaw could potentially access sensitive information processed by the service, which might include network configuration details or credentials related to wireless WAN connections.

For European organizations, the impact of CVE-2024-49103 centers on the potential exposure of sensitive information related to wireless WAN connectivity. Organizations relying on Windows 10 Version 1809 in sectors such as telecommunications, critical infrastructure, or enterprises with mobile broadband deployments could face confidentiality breaches. Information disclosure could facilitate further targeted attacks, such as network intrusion or lateral movement, especially if attackers gain physical access or leverage insider threats. The vulnerability's requirement for physical access limits remote exploitation, but in environments with shared or less controlled physical access (e.g., public sector offices, manufacturing floors, or transport hubs), the risk increases. Additionally, organizations with remote or hybrid workforces using mobile broadband devices running the affected OS version may be vulnerable. While the direct impact on system integrity and availability is low, the confidentiality breach can undermine trust, lead to regulatory non-compliance (e.g., GDPR), and cause reputational damage.

Given the absence of an official patch at the time of publication, European organizations should implement several targeted mitigations: 1) Inventory and identify all systems running Windows 10 Version 1809, particularly those utilizing WwanSvc for wireless WAN connectivity. 2) Restrict physical access to devices running the affected OS version, especially in sensitive environments, through enhanced physical security controls such as badge access, surveillance, and device locking. 3) Disable or limit the use of the Windows Wireless Wide Area Network Service on systems where it is not essential, reducing the attack surface. 4) Employ network segmentation to isolate devices with wireless WAN capabilities from critical internal networks to contain potential information disclosure. 5) Monitor logs and network traffic for unusual activity related to WwanSvc or wireless WAN connections that could indicate exploitation attempts. 6) Plan and prioritize upgrading affected systems to a supported and patched Windows version, as Windows 10 Version 1809 is nearing or past end-of-support status in many environments. 7) Educate IT staff and users about the risks associated with physical access and the importance of securing devices, especially mobile or remote endpoints.