CVE-2025-55225 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 (build 10.0.17763.0). This vulnerability allows an unauthenticated attacker to send specially crafted network packets to the RRAS service, causing it to read memory outside the intended buffer boundaries. This out-of-bounds read can disclose sensitive information from the server's memory over the network, potentially exposing confidential data such as cryptographic keys, credentials, or other sensitive information residing in memory. The vulnerability does not allow for remote code execution or denial of service but compromises confidentiality. The attack vector is network-based (AV:N), requires no privileges (PR:N), but does require user interaction (UI:R), such as the server processing malicious packets. The scope is unchanged (S:U), meaning the vulnerability affects only the vulnerable component without impacting other system components. The CVSS score of 6.5 reflects the significant confidentiality impact balanced against the need for user interaction and lack of privilege requirements. No known exploits have been reported in the wild, and no official patches have been released at the time of this report. The vulnerability was reserved in August 2025 and published in September 2025. RRAS is commonly used in enterprise environments for VPN and routing services, making this vulnerability relevant for organizations relying on Windows Server 2019 for network infrastructure.

For European organizations, the primary impact is the potential unauthorized disclosure of sensitive information from Windows Server 2019 systems running RRAS. This could lead to leakage of credentials, configuration details, or other confidential data, increasing the risk of subsequent targeted attacks such as lateral movement or privilege escalation. Organizations in sectors like finance, government, telecommunications, and critical infrastructure that depend on RRAS for secure remote access or routing are particularly vulnerable. The medium severity rating indicates that while the vulnerability is serious, it does not directly enable system takeover or service disruption. However, the confidentiality breach could undermine trust, regulatory compliance (e.g., GDPR), and operational security. Since exploitation requires network access and user interaction, exposure is higher in environments where RRAS is accessible from untrusted networks or where malicious actors can induce interaction. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially once proof-of-concept code becomes available.

1. Limit exposure of RRAS services by restricting network access to trusted IP ranges and using firewalls to block unauthorized inbound traffic. 2. Disable RRAS if it is not required or replace it with more secure VPN or routing solutions that have a smaller attack surface. 3. Monitor network traffic for unusual or malformed packets targeting RRAS ports to detect potential exploitation attempts early. 4. Implement network segmentation to isolate RRAS servers from critical assets and reduce lateral movement risk. 5. Apply principle of least privilege to accounts and services interacting with RRAS to minimize impact if compromised. 6. Prepare for patch deployment by inventorying affected systems and testing updates in controlled environments once Microsoft releases a security update. 7. Educate network administrators about this vulnerability and encourage vigilance for suspicious activity related to RRAS. 8. Use intrusion detection/prevention systems (IDS/IPS) tuned to detect anomalous RRAS traffic patterns. 9. Regularly review and update RRAS configurations to follow security best practices and minimize unnecessary features or services. 10. Maintain up-to-date backups and incident response plans to quickly recover from potential breaches stemming from this vulnerability.