CVE-2025-54097 is a medium-severity vulnerability identified as an out-of-bounds read (CWE-125) in the Windows Routing and Remote Access Service (RRAS) component of Microsoft Windows Server 2019, specifically version 10.0.17763.0. This vulnerability allows an unauthorized attacker to remotely trigger an out-of-bounds read condition, which can lead to the disclosure of sensitive information over the network. The flaw arises because RRAS improperly handles certain network packets, enabling an attacker to craft malicious packets that cause the service to read memory beyond the intended buffer boundaries. This memory disclosure can reveal sensitive data residing in adjacent memory areas, potentially including credentials, configuration data, or other critical information. The vulnerability does not require any privileges or authentication but does require user interaction, likely in the form of the victim system processing malicious network traffic. The CVSS v3.1 base score is 6.5, reflecting a medium severity with high confidentiality impact, no impact on integrity or availability, and an attack vector over the network with low attack complexity. No known exploits are currently reported in the wild, and no patches are linked yet, indicating that mitigation may rely on workarounds or monitoring until official updates are released. The vulnerability is specific to Windows Server 2019, a widely used server operating system in enterprise environments, particularly for network infrastructure roles such as RRAS, which provides routing and VPN services.

For European organizations, this vulnerability poses a risk primarily to network infrastructure relying on Windows Server 2019 RRAS deployments. Disclosure of sensitive information could lead to further targeted attacks, including credential theft or reconnaissance for lateral movement within networks. Given that RRAS is often used to provide VPN and routing services, exploitation could expose internal network details or user credentials, undermining confidentiality and potentially enabling subsequent attacks. The medium severity suggests that while the vulnerability is not immediately critical, it could be leveraged as part of a multi-stage attack chain. Organizations in sectors with strict data protection requirements, such as finance, healthcare, and government, could face compliance risks if sensitive data is leaked. Additionally, the lack of authentication requirements means attackers can attempt exploitation remotely without prior access, increasing the attack surface. However, the requirement for user interaction and the absence of known exploits reduce the immediate risk level but do not eliminate it. European entities with extensive remote access infrastructure or those using RRAS for VPN services should be particularly vigilant.

Specific mitigation steps include: 1) Immediate network-level filtering to restrict exposure of RRAS services to untrusted networks, such as blocking or limiting inbound RRAS-related traffic at firewalls or network perimeter devices. 2) Monitoring network traffic for anomalous or malformed packets targeting RRAS ports to detect potential exploitation attempts. 3) Applying the principle of least privilege and network segmentation to isolate RRAS servers from critical assets, minimizing potential impact if compromised. 4) Preparing for patch deployment by tracking Microsoft security advisories closely and testing updates in controlled environments before production rollout. 5) Employing intrusion detection and prevention systems (IDS/IPS) with updated signatures once available to detect exploitation attempts. 6) Reviewing and hardening RRAS configurations to disable unnecessary features or services that could be exploited. 7) Conducting user awareness training to reduce risky interactions that might facilitate exploitation, given the user interaction requirement. These measures go beyond generic advice by focusing on network exposure reduction, proactive monitoring, and configuration hardening specific to RRAS and Windows Server 2019 environments.