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 a buffer overflow condition. An authorized attacker with local access and limited privileges can exploit this flaw to execute arbitrary code with elevated privileges, effectively escalating their rights on the affected system. The vulnerability does not require user interaction but does require the attacker to have local access and some level of privilege, making remote exploitation less likely. The vulnerability is classified under CWE-122 (Heap-based Buffer Overflow), which typically involves overwriting adjacent memory on the heap, potentially corrupting data, control flow, or enabling code execution. The CVSS v3.1 base score is 7.0, indicating a high severity level, with attack vector local (AV:L), attack complexity high (AC:H), privileges required low (PR:L), no user interaction (UI:N), and impacts on confidentiality, integrity, and availability all rated high (C:H/I:H/A:H). No known exploits are currently reported in the wild, and no official patches have been linked yet, suggesting that mitigation may rely on workarounds or awaiting vendor updates. This vulnerability is significant because it allows privilege escalation, which can be a stepping stone for attackers to gain full control over affected systems, bypass security controls, and potentially move laterally within networks.

For European organizations, this vulnerability poses a substantial risk, especially for those still operating legacy systems such as Windows 10 Version 1809, which is an older release and may still be in use in certain sectors due to compatibility or operational constraints. Successful exploitation could allow attackers to elevate privileges from a low-level user to SYSTEM or administrative levels, enabling them to install malware, exfiltrate sensitive data, disrupt services, or establish persistent footholds. This is particularly critical for industries with stringent data protection requirements like finance, healthcare, and government institutions across Europe. The high impact on confidentiality, integrity, and availability means that exploitation could lead to data breaches, operational downtime, and regulatory non-compliance under frameworks such as GDPR. Since the attack requires local access, the threat is more pronounced in environments where endpoint security is weak, or insider threats are a concern. Additionally, the lack of known exploits in the wild provides a window for proactive defense, but the absence of patches necessitates urgent attention to mitigate risk.

European organizations should immediately identify and inventory all systems running Windows 10 Version 1809 to assess exposure. Given the absence of an official patch, organizations should implement strict access controls to limit local user privileges and restrict the ability to execute untrusted code. Employ application whitelisting to prevent unauthorized binaries from running, and enhance endpoint detection and response (EDR) capabilities to monitor for suspicious behavior indicative of privilege escalation attempts. Network segmentation can limit lateral movement if a system is compromised. Organizations should also consider upgrading affected systems to newer, supported Windows versions where this vulnerability is patched. Regularly applying security baselines and hardening guidelines for Windows 10 can reduce the attack surface. Additionally, monitoring for unusual local privilege escalation attempts in security logs and employing threat hunting focused on heap overflow exploitation techniques can provide early detection. Finally, educating users about the risks of running untrusted software locally and enforcing the principle of least privilege will reduce the likelihood of successful exploitation.