CVE-2025-29959 is a vulnerability identified in Microsoft Windows 10 Version 1809, specifically affecting the Routing and Remote Access Service (RRAS). The issue is classified under CWE-908, which pertains to the use of uninitialized resources. In this context, an uninitialized resource means that certain memory or data structures within RRAS are used before being properly initialized, potentially leading to the disclosure of sensitive information. The vulnerability allows an unauthorized attacker to remotely disclose information over the network without requiring any privileges (PR:N) but does require user interaction (UI:R), such as convincing a user to connect to a malicious RRAS server or service. The attack vector is network-based (AV:N), meaning exploitation can occur remotely without physical access. The vulnerability does not impact integrity or availability but has a high impact on confidentiality (C:H/I:N/A:N). The CVSS v3.1 base score is 6.5, indicating a medium severity level. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability could allow attackers to gain access to sensitive information that could be leveraged for further attacks or reconnaissance. Given that RRAS is often used in enterprise environments for VPN and routing services, this vulnerability could expose sensitive routing or network configuration data if exploited.

For European organizations, the impact of CVE-2025-29959 could be significant, especially for enterprises and public sector entities relying on Windows 10 Version 1809 for their network infrastructure. Disclosure of sensitive information via RRAS could lead to exposure of network topology, routing configurations, or authentication tokens, which attackers could use to facilitate lateral movement or targeted attacks. Organizations in sectors such as finance, government, healthcare, and critical infrastructure that utilize RRAS for remote access or routing services are particularly at risk. The vulnerability's remote exploitation capability means attackers can attempt to exploit it from outside the network perimeter, increasing the risk of data leakage. Although no integrity or availability impact is noted, the confidentiality breach could undermine trust, lead to regulatory non-compliance (e.g., GDPR), and cause reputational damage. Since Windows 10 Version 1809 is an older release, some organizations may still be running it due to legacy application dependencies, increasing their exposure.

1. Immediate mitigation should focus on upgrading affected systems to a supported and patched version of Windows 10 or later where this vulnerability is resolved. 2. If upgrading is not immediately possible, organizations should restrict network access to RRAS services, limiting connections to trusted hosts and networks only. 3. Implement network segmentation and firewall rules to isolate RRAS servers from untrusted networks, reducing the attack surface. 4. Monitor network traffic for unusual or unauthorized RRAS connection attempts and enable detailed logging on RRAS servers to detect potential exploitation attempts. 5. Educate users about the risks of interacting with unknown or untrusted remote access services to reduce the likelihood of user interaction exploitation. 6. Regularly review and update remote access policies, ensuring minimal exposure of RRAS services to the internet. 7. Stay alert for official patches or advisories from Microsoft and apply them promptly once available.