CVE-2025-59252 is a critical security vulnerability classified under CWE-77, indicating improper neutralization of special elements used in commands, commonly known as command injection. This vulnerability exists in Microsoft 365 Word Copilot, a feature integrated into Microsoft Word that leverages AI to assist users. The flaw allows an unauthorized attacker to inject malicious commands due to insufficient sanitization of input elements that are interpreted as commands by the system. The vulnerability is exploitable remotely over a network without requiring any privileges or user interaction, making it highly accessible to attackers. The impact primarily affects confidentiality, allowing attackers to spoof network communications and potentially intercept or manipulate sensitive data. Integrity is also partially impacted, as attackers may influence command execution flow, though availability remains unaffected. The CVSS v3.1 score of 9.3 (AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N) underscores the critical nature of this vulnerability, highlighting its ease of exploitation and severe confidentiality impact. No patches or known exploits are currently reported, but the vulnerability's presence in a widely used productivity tool raises significant concerns. The vulnerability was reserved in early September 2025 and published in October 2025, indicating recent discovery and disclosure. Organizations relying on Microsoft 365 Word Copilot should prepare for imminent patch deployment and implement interim controls to mitigate risk.

For European organizations, the impact of CVE-2025-59252 is substantial due to the widespread use of Microsoft 365 services across the continent. The vulnerability enables attackers to perform network spoofing, potentially allowing interception or redirection of sensitive communications within corporate environments. This can lead to data breaches involving confidential business information, intellectual property, or personal data protected under GDPR. The partial integrity compromise may allow attackers to manipulate document processing or command execution, undermining trust in document authenticity and workflow integrity. Given the lack of required privileges or user interaction, attackers can exploit this vulnerability at scale, increasing the risk of widespread compromise. Critical sectors such as finance, government, healthcare, and manufacturing in Europe, which heavily depend on Microsoft 365 productivity tools, face elevated risks. The potential for cross-border data exposure and disruption to collaborative workflows further exacerbates the threat landscape. Organizations may also face regulatory and reputational consequences if exploitation leads to data loss or unauthorized disclosure.

1. Monitor Microsoft’s official channels closely for patches addressing CVE-2025-59252 and prioritize immediate deployment upon release. 2. Until patches are available, restrict network access to Microsoft 365 Word Copilot services using firewall rules and network segmentation to limit exposure. 3. Implement strict input validation and command filtering at network gateways or proxy layers where feasible to detect and block suspicious command injection attempts. 4. Enhance logging and monitoring of Microsoft 365 Word Copilot usage, focusing on unusual command execution patterns or network anomalies indicative of spoofing attempts. 5. Educate IT and security teams about this vulnerability to ensure rapid incident response capabilities. 6. Employ endpoint detection and response (EDR) solutions capable of identifying abnormal process behaviors related to command injection. 7. Review and tighten access controls and permissions for Microsoft 365 services to minimize potential attack vectors. 8. Consider temporary disabling or limiting Copilot features in high-risk environments until the vulnerability is remediated. 9. Collaborate with Microsoft support for guidance on interim protective measures and best practices specific to organizational deployments.