CVE-2025-24057 is a heap-based buffer overflow vulnerability identified in Microsoft Office 2019, specifically affecting version 19.0.0. This vulnerability is classified under CWE-122, which pertains to improper memory handling leading to buffer overflows on the heap. The flaw allows an unauthorized attacker to execute arbitrary code locally on the affected system. The attack vector requires local access (AV:L), with low attack complexity (AC:L), no privileges required (PR:N), but user interaction is necessary (UI:R), such as opening a malicious Office document. The vulnerability impacts confidentiality, integrity, and availability (all rated high), meaning an attacker could potentially gain full control over the affected system, steal sensitive data, modify or delete files, or disrupt system operations. The scope is unchanged (S:U), indicating the vulnerability affects only the vulnerable component without impacting other components. The CVSS v3.1 base score is 7.8, categorizing it as a high-severity vulnerability. No known exploits are currently reported in the wild, and no official patches have been linked yet. However, given the nature of the vulnerability and the widespread use of Microsoft Office 2019, this represents a significant risk if exploited. The vulnerability was reserved in January 2025 and published in March 2025, indicating recent discovery and disclosure. The lack of required privileges and the possibility of code execution upon user interaction make this a critical concern for endpoint security, especially in environments where Office documents are frequently exchanged or opened.

For European organizations, the impact of CVE-2025-24057 could be substantial. Microsoft Office 2019 is widely used across various sectors including government, finance, healthcare, and education throughout Europe. Successful exploitation could lead to unauthorized code execution on user machines, potentially allowing attackers to deploy malware, ransomware, or conduct espionage activities. This could result in data breaches involving personal data protected under GDPR, leading to regulatory penalties and reputational damage. The high impact on confidentiality, integrity, and availability means critical business operations could be disrupted. Additionally, since exploitation requires user interaction, phishing or social engineering campaigns could be leveraged to trigger the vulnerability, increasing the risk in environments with less mature security awareness. The absence of known exploits in the wild currently provides a window for proactive mitigation, but the high severity score necessitates immediate attention to prevent future exploitation.

European organizations should implement targeted mitigation strategies beyond generic advice: 1) Prioritize patch management by monitoring Microsoft security advisories for the release of official patches addressing CVE-2025-24057 and apply them promptly. 2) Implement application control policies to restrict execution of unauthorized or suspicious Office macros and scripts. 3) Enhance email filtering and attachment scanning to detect and block malicious Office documents that could trigger the vulnerability. 4) Conduct user awareness training focused on recognizing phishing attempts and the risks of opening unsolicited or unexpected Office files. 5) Utilize endpoint detection and response (EDR) tools to monitor for anomalous behaviors indicative of exploitation attempts, such as unusual memory usage or process spawning from Office applications. 6) Consider deploying sandboxing solutions for opening Office documents in isolated environments to prevent local system compromise. 7) Review and restrict local user privileges where possible to limit the impact of local code execution. These measures collectively reduce the attack surface and improve detection and response capabilities against exploitation attempts.