CVE-2025-53147 is a use-after-free vulnerability classified under CWE-416 affecting the Windows Ancillary Function Driver for WinSock component in Microsoft Windows 10 Version 1809 (build 10.0.17763.0). This vulnerability occurs when the driver improperly manages memory, leading to a scenario where freed memory is accessed, potentially allowing an attacker to execute arbitrary code or cause system instability. The flaw specifically enables an authorized local attacker—someone with limited privileges on the affected system—to elevate their privileges to higher levels, such as SYSTEM or administrator, without requiring any user interaction. The vulnerability's CVSS 3.1 base score is 7.0, indicating high severity, with attack vector local (AV:L), attack complexity high (AC:H), privileges required low (PR:L), no user interaction (UI:N), and impact on confidentiality, integrity, and availability all rated high (C:H/I:H/A:H). The vulnerability was published on August 12, 2025, with no known exploits in the wild at the time of disclosure. The absence of a patch link suggests that a fix may be pending or in development. The vulnerability could be exploited by attackers who have gained local access through other means, such as phishing or physical access, to escalate privileges and gain full control over the system. This can lead to unauthorized data access, system manipulation, or denial of service. The Ancillary Function Driver for WinSock is a critical component managing network socket operations, so exploitation could also impact network communications.

For European organizations, this vulnerability poses a significant risk, particularly for those still operating legacy Windows 10 Version 1809 systems, which may be common in industrial, governmental, or enterprise environments with slower upgrade cycles. Successful exploitation can lead to full system compromise, allowing attackers to bypass security controls, access sensitive data, disrupt services, or deploy further malware. Critical infrastructure sectors such as energy, finance, healthcare, and government agencies are especially vulnerable due to the potential for cascading effects from compromised systems. The local attack vector means that insider threats or attackers who have already breached perimeter defenses can leverage this vulnerability to escalate privileges and move laterally within networks. The lack of user interaction requirement increases the risk of automated or stealthy exploitation once local access is obtained. The high impact on confidentiality, integrity, and availability underscores the potential for severe operational and reputational damage.

Immediate mitigation should focus on limiting local access to systems running Windows 10 Version 1809 by enforcing strict access controls and monitoring for suspicious local activity. Organizations should prioritize upgrading affected systems to supported Windows versions with active security updates. Until patches are released, deploying endpoint detection and response (EDR) solutions capable of identifying anomalous behavior related to memory corruption or privilege escalation attempts is critical. Network segmentation can reduce the risk of lateral movement post-exploitation. Administrators should audit and restrict the use of accounts with local privileges and implement application whitelisting to prevent unauthorized code execution. Regularly reviewing logs for signs of exploitation attempts and educating users about the risks of local compromise can further reduce exposure. Once Microsoft releases a security update, prompt deployment is essential. Additionally, employing exploit mitigation technologies such as Control Flow Guard (CFG) and Data Execution Prevention (DEP) can help reduce the likelihood of successful exploitation.