CVE-2025-58734 is a use-after-free vulnerability classified under CWE-416 affecting Microsoft Windows 11 Version 25H2 (build 10.0.26200.0). The flaw exists within Inbox COM Objects, which are components used for inter-process communication and system functionality. A use-after-free occurs when a program continues to use a pointer after the memory it points to has been freed, leading to undefined behavior including potential code execution. In this case, an unauthorized attacker with local access can exploit this vulnerability to execute arbitrary code on the affected system. The CVSS v3.1 base score is 7.0, indicating high severity, with vector metrics AV:L (local attack vector), AC:H (high attack complexity), PR:N (no privileges required), UI:R (requires user interaction), S:U (unchanged scope), and full impact on confidentiality, integrity, and availability (C:H/I:H/A:H). The attack complexity is high, meaning exploitation requires specific conditions or knowledge, and user interaction is necessary, such as convincing a user to open a malicious file or perform an action triggering the vulnerability. No patches or known exploits are currently reported, but the vulnerability is publicly disclosed and should be addressed promptly. The vulnerability could allow attackers to escalate privileges or execute arbitrary code leading to full system compromise, data theft, or disruption of services.

For European organizations, this vulnerability poses a significant risk due to the widespread adoption of Windows 11 in enterprise environments. Successful exploitation could lead to unauthorized code execution, allowing attackers to gain control over affected systems, steal sensitive data, disrupt operations, or deploy ransomware. Critical sectors such as finance, healthcare, government, and infrastructure could face severe operational and reputational damage. The requirement for local access and user interaction somewhat limits remote exploitation but does not eliminate risk, especially in environments with shared workstations or where social engineering could be used. The high impact on confidentiality, integrity, and availability means that exploitation could result in data breaches, system downtime, and loss of trust. Additionally, the lack of known exploits currently reduces immediate risk but also means organizations must proactively prepare for potential future attacks once exploit code becomes available.

1. Monitor Microsoft security advisories closely and apply official patches or updates as soon as they are released to remediate the vulnerability. 2. Restrict local access to critical systems by enforcing strict access controls, limiting physical and remote desktop access to authorized personnel only. 3. Implement user training and awareness programs to reduce the risk of social engineering attacks that could trigger user interaction required for exploitation. 4. Use application whitelisting and endpoint protection solutions capable of detecting anomalous behavior related to COM object misuse or memory corruption. 5. Employ network segmentation to isolate sensitive systems and reduce the attack surface. 6. Regularly audit and monitor logs for unusual activity indicative of exploitation attempts, such as unexpected process creation or privilege escalations. 7. Disable or limit use of Inbox COM Objects where feasible, or apply configuration hardening to reduce exposure. 8. Maintain up-to-date backups and incident response plans to quickly recover from potential compromises.