CVE-2025-58735 is a use-after-free vulnerability classified under CWE-416 affecting Inbox COM Objects in Microsoft Windows 11 Version 25H2 (build 10.0.26200.0). Use-after-free occurs when a program continues to use memory after it has been freed, leading to undefined behavior such as arbitrary code execution. In this case, the vulnerability allows an unauthorized attacker with local access to execute code by triggering the flaw in the COM objects, which are components used for interprocess communication and object creation in Windows. The CVSS 3.1 vector indicates the attack requires local access (AV:L), has high attack complexity (AC:H), no privileges required (PR:N), but does require user interaction (UI:R). The scope is unchanged (S:U), and the impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H). The vulnerability was reserved on 2025-09-03 and published on 2025-10-14, with no known exploits in the wild yet. The lack of patches at the time of reporting means organizations must be vigilant. The vulnerability could be exploited by convincing a user to perform an action that triggers the use-after-free condition in the Inbox COM objects, potentially leading to full system compromise. This vulnerability is particularly dangerous because it does not require elevated privileges, making it easier for attackers with local access to escalate their control. The Inbox COM objects are part of the Windows system components, so exploitation could affect a wide range of applications and services relying on these objects.

For European organizations, this vulnerability poses a significant risk due to the widespread use of Windows 11 25H2 in enterprise and government environments. Successful exploitation could lead to arbitrary code execution, allowing attackers to install malware, steal sensitive data, disrupt operations, or move laterally within networks. Confidentiality, integrity, and availability of critical systems could be severely impacted. Sectors such as finance, healthcare, energy, and government agencies are particularly at risk due to the sensitivity of their data and the critical nature of their operations. The requirement for local access and user interaction somewhat limits remote exploitation but does not eliminate risk, especially in environments where insider threats or phishing attacks are possible. The absence of known exploits currently provides a window for proactive mitigation, but the high severity score indicates that once exploited, the damage could be extensive.

1. Apply official Microsoft patches immediately once they become available to address CVE-2025-58735. 2. Until patches are released, restrict local user permissions to the minimum necessary to reduce the risk of unauthorized code execution. 3. Implement application whitelisting and endpoint protection solutions that can detect and block suspicious COM object usage or memory corruption attempts. 4. Educate users about the risks of interacting with untrusted content or executing unknown applications to reduce the likelihood of triggering the vulnerability. 5. Monitor system logs and security telemetry for unusual activity related to COM objects or unexpected process behavior. 6. Employ network segmentation to limit the spread of potential compromises originating from local exploitation. 7. Use advanced threat detection tools capable of identifying exploitation techniques related to use-after-free vulnerabilities. 8. Regularly review and update security policies to incorporate emerging threats and ensure rapid response capabilities.