CVE-2025-50155 is a high-severity local privilege escalation vulnerability affecting Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The vulnerability arises from a type confusion issue (CWE-843) within the Windows Push Notifications component. Type confusion occurs when a program accesses a resource using an incompatible type, leading to unexpected behavior or memory corruption. In this case, an authorized attacker with limited privileges on the affected system can exploit this flaw to elevate their privileges locally, potentially gaining higher-level access such as SYSTEM or administrator rights. The vulnerability does not require user interaction and has a low attack complexity, but it does require the attacker to have some level of existing privileges (PR:L). The CVSS 3.1 base score is 7.8, reflecting high impact on confidentiality, integrity, and availability (all rated high). Although no public exploits are currently known in the wild, the vulnerability is critical for environments still running Windows 10 Version 1809, which is an older but still operational release in some organizations. The lack of available patches at the time of publication increases the urgency for mitigation. This vulnerability could be leveraged by attackers to bypass security controls, install persistent malware, or move laterally within a network after initial access. Given the nature of the flaw in a core Windows component, exploitation could lead to full system compromise.

For European organizations, the impact of CVE-2025-50155 can be significant, especially for those still operating legacy systems like Windows 10 Version 1809. Successful exploitation allows attackers to escalate privileges locally, which can facilitate the deployment of ransomware, data exfiltration, or sabotage of critical infrastructure. Organizations in sectors such as finance, healthcare, manufacturing, and government are particularly at risk due to the sensitive nature of their data and the criticality of their operations. The vulnerability undermines the confidentiality, integrity, and availability of affected systems, potentially leading to severe operational disruptions and regulatory compliance issues under frameworks like GDPR. Since the vulnerability requires local access, initial compromise vectors such as phishing or insider threats could be leveraged to exploit this flaw. The absence of known exploits in the wild currently provides a window for proactive defense, but the high severity score indicates that once exploits become available, rapid exploitation could occur. European organizations with distributed endpoints running outdated Windows versions are at heightened risk, necessitating immediate attention to mitigate potential damage.

1. Immediate upgrade or patching: Although no patches are listed at the time of this report, organizations should monitor Microsoft’s official channels for security updates addressing CVE-2025-50155 and apply them promptly once available. 2. System upgrade: Consider upgrading affected systems from Windows 10 Version 1809 to a supported and more secure Windows version (e.g., Windows 10 22H2 or Windows 11) to reduce exposure to legacy vulnerabilities. 3. Privilege restriction: Enforce the principle of least privilege rigorously to limit the number of users and processes with elevated rights, reducing the potential impact of local privilege escalation. 4. Application whitelisting and endpoint protection: Deploy advanced endpoint detection and response (EDR) solutions capable of detecting abnormal privilege escalation attempts and block unauthorized code execution. 5. Network segmentation: Isolate critical systems and sensitive data environments to contain potential lateral movement following exploitation. 6. Audit and monitoring: Enable detailed logging of privilege escalation attempts and monitor for suspicious activity indicative of exploitation attempts. 7. User training: Educate users about phishing and social engineering risks that could lead to initial local access, which is a prerequisite for exploiting this vulnerability. 8. Disable or restrict Windows Push Notifications where feasible, especially on high-risk or sensitive systems, to reduce the attack surface related to this component.