CVE-2025-29967 is a high-severity heap-based buffer overflow vulnerability identified in the Microsoft Windows App Client for Windows Desktop, specifically within the Remote Desktop Gateway Service component. This vulnerability, classified under CWE-122, allows an unauthorized attacker to execute arbitrary code remotely over a network without requiring prior authentication. The flaw arises due to improper handling of memory buffers on the heap, which can be exploited by sending specially crafted requests to the vulnerable service. Successful exploitation could lead to full compromise of the affected system, allowing attackers to execute code with the privileges of the Remote Desktop Gateway Service, potentially leading to system takeover, data theft, or disruption of services. The CVSS v3.1 base score of 8.8 reflects the critical nature of this vulnerability, highlighting its high impact on confidentiality, integrity, and availability, combined with ease of exploitation (network vector, no privileges required, but user interaction is needed). Although no known exploits are currently reported in the wild, the vulnerability's characteristics make it a prime target for attackers once exploit code becomes available. The affected product version is 1.00 of the Windows App Client for Windows Desktop, indicating that organizations using this specific version are at risk. Given the Remote Desktop Gateway Service's role in enabling secure remote access, this vulnerability poses a significant threat to enterprise environments relying on remote desktop solutions for operational continuity.

For European organizations, the impact of CVE-2025-29967 could be severe. Many enterprises and public sector entities across Europe utilize Microsoft Windows environments with Remote Desktop Gateway Services to facilitate remote work, especially in the context of increased remote operations post-pandemic. Exploitation of this vulnerability could lead to unauthorized access to sensitive corporate networks, data breaches involving personal and financial information protected under GDPR, and disruption of critical services. The ability to execute arbitrary code remotely without authentication increases the risk of widespread ransomware attacks, espionage, or sabotage. Additionally, compromised systems could be used as pivot points to infiltrate deeper into organizational networks, affecting supply chains and critical infrastructure. The potential for service outages could impact sectors such as finance, healthcare, government, and manufacturing, all vital to European economies and public welfare.

To mitigate this vulnerability effectively, European organizations should prioritize the following actions: 1) Immediate deployment of official patches or updates from Microsoft once available; since no patch links are currently provided, organizations should monitor Microsoft security advisories closely. 2) Implement network-level protections such as restricting Remote Desktop Gateway access to trusted IP addresses and using VPNs or zero-trust network access solutions to limit exposure. 3) Employ robust intrusion detection and prevention systems (IDS/IPS) to monitor and block suspicious traffic targeting Remote Desktop Gateway Services. 4) Enforce multi-factor authentication (MFA) for remote access to add an additional security layer, even though the vulnerability does not require authentication, to reduce overall attack surface. 5) Conduct regular security audits and vulnerability assessments focusing on remote access infrastructure. 6) Educate IT staff and users about the risks and signs of exploitation attempts, including monitoring for unusual Remote Desktop activity. 7) Consider network segmentation to isolate Remote Desktop Gateway Services from critical internal resources, limiting lateral movement in case of compromise.