CVE-2025-62549 is a vulnerability classified under CWE-822 (Untrusted Pointer Dereference) affecting Microsoft Windows 10 Version 1809, specifically the Routing and Remote Access Service (RRAS). The flaw arises when RRAS improperly handles pointers from untrusted sources, leading to dereferencing invalid or maliciously crafted pointers. This can cause memory corruption, enabling an attacker to execute arbitrary code remotely over the network without requiring any privileges or prior authentication. The attack vector is network-based (AV:N), with low attack complexity (AC:L), and requires user interaction (UI:R), such as the victim initiating a connection or interaction that triggers the vulnerability. The vulnerability impacts confidentiality, integrity, and availability (all high), potentially allowing full system compromise, data theft, or denial of service. The CVSS v3.1 base score is 8.8, indicating high severity. The vulnerability was reserved in mid-October 2025 and published in early December 2025. No known exploits have been reported in the wild yet, but the nature of the flaw and affected service make it a critical concern. RRAS is commonly used to provide VPN, dial-up, and routing services, meaning that systems exposing RRAS to untrusted networks are particularly at risk. The lack of an available patch link suggests that mitigation may currently rely on workarounds or configuration changes until an official fix is released.

For European organizations, this vulnerability poses a significant risk, especially for enterprises and public sector entities that use Windows 10 Version 1809 with RRAS enabled for remote access or routing services. Successful exploitation could lead to unauthorized remote code execution, allowing attackers to gain control over affected systems, steal sensitive data, disrupt network services, or pivot within internal networks. Critical infrastructure sectors such as energy, finance, healthcare, and government agencies that rely on RRAS for secure remote connectivity are particularly vulnerable. The compromise of such systems could result in operational disruptions, data breaches, and reputational damage. Since the vulnerability requires no authentication and has low attack complexity, it could be exploited by a wide range of threat actors, including cybercriminals and state-sponsored groups. The impact is exacerbated by the fact that Windows 10 Version 1809 is an older release, which may still be in use in legacy environments across Europe, increasing the attack surface.

1. Immediately audit all systems running Windows 10 Version 1809 to identify those with RRAS enabled and exposed to untrusted networks. 2. Where possible, disable RRAS services on systems that do not require them to reduce the attack surface. 3. Implement strict network segmentation and firewall rules to restrict access to RRAS services only to trusted internal networks or VPN endpoints. 4. Monitor network traffic for unusual or malformed packets targeting RRAS ports and protocols, using intrusion detection/prevention systems (IDS/IPS) with updated signatures. 5. Educate users about the risk of interacting with untrusted networks or initiating connections that could trigger the vulnerability. 6. Prepare for patch deployment by testing updates in controlled environments once Microsoft releases official patches; prioritize rapid deployment upon availability. 7. Consider upgrading affected systems to a supported and patched version of Windows 10 or later to eliminate exposure to this vulnerability. 8. Employ endpoint detection and response (EDR) tools to detect potential exploitation attempts and anomalous behavior related to RRAS processes.