CVE-2025-62554 is a vulnerability classified under CWE-843 (Access of Resource Using Incompatible Type, or type confusion) affecting Microsoft Office LTSC 2024 version 16.0.0. This vulnerability allows an attacker to execute arbitrary code locally by exploiting the way Office handles resource types internally. Type confusion occurs when a program accesses a resource assuming it is of one type, but it is actually of another incompatible type, leading to memory corruption or unexpected behavior. In this case, the flaw enables an attacker without any privileges or user interaction to execute code with the same permissions as the current user. The vulnerability has a CVSS v3.1 base score of 8.4, indicating high severity, with metrics showing local attack vector, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality, integrity, and availability. Although no public exploits are known yet, the vulnerability poses a significant risk due to the widespread use of Microsoft Office in enterprise environments. The lack of available patches at the time of publication necessitates immediate attention to mitigate potential exploitation. The vulnerability could be leveraged by malicious insiders or malware that gains local access to execute arbitrary code, potentially leading to data breaches, system compromise, or disruption of business operations.

For European organizations, the impact of CVE-2025-62554 is considerable. Microsoft Office is a ubiquitous productivity suite across Europe, used in government, finance, healthcare, education, and critical infrastructure sectors. Successful exploitation could lead to unauthorized code execution, enabling attackers to steal sensitive data, install persistent malware, or disrupt operations. The vulnerability affects confidentiality by allowing access to protected information, integrity by enabling unauthorized code execution that can modify data or system state, and availability by potentially causing system crashes or denial of service. Given that no user interaction or privileges are required, the attack surface is broad, especially in environments where local access controls are weak or endpoint security is insufficient. This elevates the risk for organizations with remote or shared workstations, or those using virtual desktop infrastructure. The absence of known exploits currently provides a window for proactive mitigation, but the potential for rapid weaponization exists due to the high severity and ease of exploitation.

1. Monitor Microsoft’s official security advisories closely and apply patches immediately once released for Microsoft Office LTSC 2024 version 16.0.0. 2. Restrict local access to systems running the vulnerable Office version by enforcing strict access controls and limiting administrative privileges. 3. Employ application whitelisting and endpoint detection and response (EDR) solutions to detect and block suspicious activities indicative of exploitation attempts. 4. Conduct regular audits of installed software versions across the enterprise to identify and remediate vulnerable Office installations. 5. Educate users about the risks of local malware and enforce policies to prevent unauthorized software execution. 6. Use virtualization or sandboxing techniques for opening untrusted Office documents to contain potential exploitation. 7. Implement network segmentation to limit lateral movement if an endpoint is compromised. 8. Maintain up-to-date backups and incident response plans to quickly recover from potential breaches.