CVE-2025-49702 is a high-severity vulnerability classified as CWE-843 (Access of Resource Using Incompatible Type, commonly known as 'Type Confusion') affecting Microsoft Office 2019 version 19.0.0. This vulnerability arises when Microsoft Office improperly handles data types internally, allowing an attacker to access resources using an incompatible type. This type confusion flaw can lead to memory corruption, enabling an unauthorized attacker to execute arbitrary code locally on the affected system. The vulnerability requires local access to the system (Attack Vector: Local), does not require privileges (Privileges Required: None), but does require user interaction (User Interaction: Required), such as opening a malicious Office document. The scope is unchanged, meaning the vulnerability affects only the vulnerable component without impacting other components. The impact on confidentiality, integrity, and availability is high, indicating that successful exploitation can lead to full system compromise, including data theft, modification, or denial of service. No known exploits are currently reported in the wild, and no patches have been linked yet, suggesting that organizations should prioritize monitoring and mitigation efforts. The vulnerability was published on July 8, 2025, with a CVSS v3.1 score of 7.8, reflecting its high severity. The technical root cause is a type confusion error, a common memory safety issue where the program treats a piece of memory as a different type than it actually is, leading to unpredictable behavior and potential code execution.

For European organizations, this vulnerability poses a significant risk due to the widespread use of Microsoft Office 2019 in enterprise, government, and educational environments. Successful exploitation could allow attackers to execute arbitrary code locally, potentially leading to data breaches, ransomware deployment, or lateral movement within networks. Confidentiality could be compromised by unauthorized data access, integrity by unauthorized modification of documents or system files, and availability by causing system crashes or denial of service. Since exploitation requires user interaction, phishing or social engineering campaigns distributing malicious Office documents could be effective attack vectors. The lack of required privileges lowers the barrier for attackers once a user opens a malicious file. Given the critical role of Office in daily operations, disruption or compromise could have cascading effects on business continuity and regulatory compliance, especially under GDPR and other data protection laws. The absence of known exploits in the wild provides a window for proactive defense, but organizations should act swiftly to mitigate risks.

1. Implement strict email filtering and attachment scanning to detect and block malicious Office documents before reaching end users. 2. Educate users on the risks of opening unsolicited or unexpected Office files, emphasizing caution with email attachments and links. 3. Employ application whitelisting and sandboxing techniques to restrict execution of untrusted Office macros or embedded code. 4. Use endpoint detection and response (EDR) solutions to monitor for suspicious behavior indicative of exploitation attempts. 5. Regularly update and patch Microsoft Office as soon as official fixes become available from Microsoft. 6. Disable or restrict Office features that allow embedded code execution, such as macros, where business needs permit. 7. Enforce the principle of least privilege on user accounts to limit the impact of local code execution. 8. Maintain comprehensive backups and incident response plans to recover quickly from potential compromises. These measures go beyond generic advice by focusing on layered defenses tailored to the attack vector and exploitation method specific to this vulnerability.