CVE-2025-49744 is a heap-based buffer overflow vulnerability identified in the Microsoft Graphics Component of Windows 10 Version 1809 (build 10.0.17763.0). This vulnerability arises due to improper handling of memory allocation on the heap, which can lead to an overflow condition when processing certain graphics-related data. An attacker with authorized local access (i.e., a user with limited privileges) can exploit this flaw to execute arbitrary code with elevated privileges, effectively escalating their permissions on the affected system. The vulnerability does not require user interaction beyond the attacker’s initial local access and has a high complexity barrier (AC:H) for exploitation, indicating that successful exploitation demands significant effort or specific conditions. The CVSS v3.1 base score is 7.0, reflecting high severity with impacts on confidentiality, integrity, and availability (all rated high). Although no known exploits are currently observed in the wild, the vulnerability poses a significant risk due to the potential for privilege escalation, which can be leveraged to gain full control over the system. The absence of published patches at the time of disclosure increases the urgency for mitigation and monitoring. This vulnerability is categorized under CWE-122 (Heap-based Buffer Overflow), which is a common and dangerous class of memory corruption bugs that can lead to arbitrary code execution, denial of service, or system compromise.

For European organizations, this vulnerability presents a critical risk primarily in environments where Windows 10 Version 1809 is still in use, particularly in legacy systems or specialized industrial setups that have not been upgraded. Successful exploitation could allow attackers to escalate privileges from a low-privileged user account to SYSTEM or equivalent, enabling full control over the affected machine. This could lead to unauthorized access to sensitive data, disruption of business operations, deployment of malware or ransomware, and lateral movement within corporate networks. Given the high confidentiality, integrity, and availability impacts, organizations in sectors such as finance, healthcare, critical infrastructure, and government are at heightened risk. The local attack vector means that insider threats or attackers who have gained initial footholds via phishing or other means could leverage this vulnerability to deepen their access. The lack of known exploits in the wild currently reduces immediate risk but does not eliminate the threat, as weaponization could occur rapidly once details are widely disseminated.

European organizations should prioritize upgrading or patching affected systems as soon as Microsoft releases an official security update for this vulnerability. In the interim, organizations should: 1) Audit and inventory all systems running Windows 10 Version 1809 to identify vulnerable endpoints. 2) Restrict local user privileges and enforce the principle of least privilege to minimize the number of users who can execute code locally. 3) Employ application whitelisting and endpoint detection and response (EDR) solutions to monitor for suspicious activity indicative of exploitation attempts. 4) Harden systems by disabling or restricting access to the Microsoft Graphics Component where feasible, or applying mitigations such as Data Execution Prevention (DEP) and Address Space Layout Randomization (ASLR) if not already enabled. 5) Increase monitoring of local privilege escalation attempts in security logs and SIEM systems. 6) Educate users about the risks of executing untrusted code locally and enforce strict controls on software installation and execution. 7) Plan for timely migration to supported Windows versions beyond 1809, as extended support for this version is limited and security updates may be delayed or unavailable.