CVE-2025-53140 is a high-severity use-after-free vulnerability (CWE-416) found in the Kernel Transaction Manager component of Microsoft Windows 10 Version 1809 (build 10.0.17763.0). This vulnerability allows an authorized local attacker to elevate privileges by exploiting improper handling of kernel memory, specifically through a use-after-free condition. In such a scenario, the attacker triggers the system to free a memory object while it is still in use, leading to potential corruption of kernel memory. This corruption can be leveraged to execute arbitrary code or escalate privileges from a lower-privileged user context to SYSTEM level. The vulnerability requires local access with some privileges (PR:L) and has a high attack complexity (AC:H), meaning exploitation is not trivial but feasible with sufficient knowledge. No user interaction is required (UI:N), and the scope is unchanged (S:U), indicating the vulnerability affects only the vulnerable component without impacting other system components. The CVSS v3.1 score is 7.0, reflecting high impact on confidentiality, integrity, and availability (C:H/I:H/A:H). No known exploits are currently reported in the wild, and no patches have been linked yet, which suggests that organizations running this specific Windows 10 version remain at risk until a fix is released. The vulnerability is particularly critical because kernel-level exploits can bypass many security controls and lead to full system compromise.

For European organizations, this vulnerability poses a significant risk, especially for enterprises and government agencies still operating legacy Windows 10 Version 1809 systems. Successful exploitation could allow attackers with local access—such as malicious insiders or attackers who have gained limited foothold through phishing or other means—to escalate privileges to SYSTEM level, enabling full control over affected machines. This could lead to data breaches, deployment of ransomware, lateral movement within networks, and disruption of critical services. Given the kernel-level nature of the flaw, traditional endpoint protections may be bypassed, increasing the risk of persistent and stealthy attacks. Organizations in sectors with strict data protection regulations, such as finance, healthcare, and public administration, could face severe compliance and reputational consequences if exploited. The lack of known exploits in the wild currently provides a window for proactive mitigation, but the high severity demands urgent attention to prevent future exploitation.

1. Immediate mitigation should focus on identifying and inventorying all systems running Windows 10 Version 1809 (build 17763.0) within the organization. 2. Restrict local access to these systems to trusted users only, employing strict access controls and monitoring for unusual privilege escalation attempts. 3. Implement application whitelisting and endpoint detection and response (EDR) solutions capable of detecting anomalous kernel-level activities. 4. Employ network segmentation to limit lateral movement in case of compromise. 5. Regularly audit and harden user privileges to minimize the number of users with local access rights. 6. Monitor security advisories from Microsoft closely for the release of patches or workarounds and prioritize patch deployment as soon as available. 7. Consider upgrading affected systems to a supported and patched Windows version where feasible, as Windows 10 Version 1809 is an older release with limited support. 8. Conduct user awareness training to reduce the risk of initial foothold via social engineering, which could lead to local access. These steps go beyond generic advice by focusing on access control, monitoring, and proactive system upgrades tailored to this specific kernel-level vulnerability.