CVE-2025-29836 is a security vulnerability classified as CWE-125 (Out-of-bounds Read) found in the Windows Routing and Remote Access Service (RRAS) component of Microsoft Windows 10 Version 1507 (build 10.0.10240.0). The flaw arises due to improper bounds checking when RRAS processes certain network inputs, allowing an attacker to read memory outside the intended buffer boundaries. This out-of-bounds read can lead to unauthorized disclosure of sensitive information over the network. The vulnerability can be exploited remotely without requiring any privileges (AV:N/PR:N), but user interaction is necessary (UI:R), such as convincing a user to connect to a malicious network or service. The scope is unchanged (S:U), meaning the impact is limited to the vulnerable component. The confidentiality impact is high (C:H), while integrity and availability are unaffected (I:N/A:N). The CVSS 3.1 base score is 6.5, reflecting a medium severity. No patches or exploits are currently publicly available, but the vulnerability is officially published and recognized by Microsoft and CISA. The affected Windows version is an early release of Windows 10, which is mostly superseded by newer versions but may still be in use in legacy environments. RRAS is commonly used to provide VPN and routing services, making this vulnerability relevant in network perimeter and remote access scenarios. Attackers exploiting this flaw could gain access to sensitive memory contents, potentially including credentials or configuration data, leading to further compromise or information leakage. Organizations running this Windows version with RRAS enabled should prioritize mitigation to prevent data exposure.

For European organizations, the primary impact of CVE-2025-29836 is the potential unauthorized disclosure of sensitive information due to the out-of-bounds read in RRAS. This can compromise confidentiality, especially if RRAS is used to facilitate VPN or remote access connections, exposing internal network details or credentials. While the vulnerability does not affect integrity or availability, leaked information could enable subsequent attacks such as privilege escalation or lateral movement. Organizations relying on legacy Windows 10 Version 1507 systems, particularly in critical infrastructure sectors like energy, finance, or government, may face increased risk if these systems are exposed to untrusted networks. The medium severity score indicates a moderate risk, but the lack of required privileges lowers the barrier for attackers. However, the need for user interaction somewhat limits exploitation scenarios. The absence of known exploits reduces immediate threat but does not eliminate future risk. Overall, the vulnerability could lead to data breaches, regulatory non-compliance (e.g., GDPR), and reputational damage if exploited in European contexts.

1. Upgrade all affected systems from Windows 10 Version 1507 to a supported and fully patched Windows version to eliminate the vulnerability. 2. Disable or restrict the use of RRAS where it is not essential, especially on systems exposed to untrusted networks. 3. Implement network segmentation and firewall rules to limit RRAS traffic to trusted endpoints only. 4. Monitor network traffic for unusual RRAS connection attempts or anomalous data patterns indicative of exploitation attempts. 5. Educate users about the risks of connecting to untrusted networks or services that could trigger user interaction exploitation vectors. 6. Employ endpoint detection and response (EDR) solutions to detect suspicious memory access patterns or abnormal RRAS behavior. 7. Maintain an inventory of legacy systems and plan for their timely decommissioning or upgrade to reduce exposure. 8. Apply network intrusion detection systems (NIDS) with signatures or heuristics tuned to detect RRAS-related exploits once available. 9. Coordinate with Microsoft support and subscribe to security advisories for updates or patches related to this vulnerability. 10. Conduct regular security assessments and penetration tests focusing on remote access services to identify and remediate similar weaknesses.