CVE-2025-58738 is a use-after-free vulnerability classified under CWE-416 affecting the Inbox COM Objects in Microsoft Windows 11 Version 25H2 (build 10.0.26200.0). Use-after-free vulnerabilities occur when a program continues to use a pointer after the memory it points to has been freed, leading to undefined behavior including potential arbitrary code execution. In this case, an unauthorized attacker with local access can exploit this flaw to execute code with the privileges of the current user. The vulnerability requires user interaction, such as opening a specially crafted file or triggering a specific action that interacts with the vulnerable COM object. The CVSS v3.1 base score is 7.0, indicating high severity, with the vector AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H, meaning the attack requires local access, high attack complexity, no privileges required, user interaction, unchanged scope, and impacts confidentiality, integrity, and availability to a high degree. No patches or known exploits are currently available, but the vulnerability is publicly disclosed and should be considered a significant risk. The vulnerability could allow attackers to execute arbitrary code, potentially leading to full system compromise, data theft, or disruption of services. Given the widespread deployment of Windows 11 in enterprise environments, this vulnerability represents a critical local attack vector that could be leveraged in targeted attacks or by malicious insiders.

For European organizations, this vulnerability poses a significant risk because it allows local attackers to gain arbitrary code execution, potentially leading to full system compromise. This could result in data breaches, disruption of critical services, and loss of confidentiality, integrity, and availability of sensitive information. Organizations with high-value targets, such as financial institutions, government agencies, healthcare providers, and critical infrastructure operators, are particularly vulnerable. The requirement for local access and user interaction limits remote exploitation but does not eliminate risk, especially in environments where insider threats or compromised endpoints are possible. The lack of an available patch increases exposure time, and attackers could develop exploits once the vulnerability details are widely known. Additionally, the impact on availability could disrupt business operations, causing financial and reputational damage. The vulnerability could also be chained with other exploits to escalate privileges or move laterally within networks, amplifying its impact.

1. Restrict local user privileges to the minimum necessary to reduce the risk of exploitation by unauthorized users. 2. Implement strict application whitelisting and endpoint protection to detect and block suspicious activities related to COM objects. 3. Use network segmentation and access controls to limit the ability of attackers to reach vulnerable systems locally. 4. Educate users about the risks of interacting with untrusted files or applications that could trigger the vulnerability. 5. Monitor system logs and behavior for anomalies indicative of exploitation attempts, such as unexpected COM object usage or crashes. 6. Prepare for rapid deployment of official patches once released by Microsoft by maintaining an up-to-date asset inventory and patch management process. 7. Employ advanced threat detection solutions that can identify use-after-free exploitation techniques. 8. Consider temporary workarounds such as disabling or restricting the vulnerable Inbox COM Objects if feasible and without impacting business operations. 9. Conduct regular security audits and penetration tests focusing on local privilege escalation vectors to identify and remediate similar weaknesses.