CVE-2025-21365 in Office
Summary
by MITRE • 01/14/2025
Microsoft Office Remote Code Execution Vulnerability
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Analysis
by VulDB Data Team • 06/21/2026
Microsoft Office remote code execution vulnerabilities represent critical security flaws that allow attackers to execute arbitrary code on affected systems without user interaction or authentication. These vulnerabilities typically arise from insufficient input validation and memory corruption issues within Microsoft Office applications such as Word, Excel, PowerPoint, and Outlook. The technical nature of these flaws often involves buffer overflows, use-after-free conditions, or improper handling of specially crafted malicious files that trigger unexpected behavior in the application's processing routines.
The exploitation of these vulnerabilities commonly occurs through social engineering techniques where users open malicious Office documents attached to emails or downloaded from compromised websites. Attackers craft documents containing malicious embedded content or malformed data structures that cause the Office application to behave unpredictably when parsing the file. These flaws can be leveraged to gain unauthorized access to systems, escalate privileges, and establish persistent footholds within network environments. The impact extends beyond individual system compromise as these vulnerabilities can facilitate lateral movement and broader network infiltration when exploited in targeted attacks.
From a cybersecurity perspective, these vulnerabilities align with CWE-121 and CWE-122 categories related to buffer overflow conditions and heap-based buffer overflows, respectively. The ATT&CK framework categorizes these exploits under initial access and execution techniques, specifically leveraging malicious files and documents as delivery mechanisms. The Office applications present particularly attractive targets due to their widespread use across enterprises and the high likelihood that users will interact with potentially malicious documents. Organizations frequently experience successful exploitation attempts when employees open compromised Office files, making these vulnerabilities among the most commonly exploited threats in enterprise environments.
Mitigation strategies for these vulnerabilities typically involve immediate patch management and application of security updates from Microsoft. Organizations should implement strict email filtering and web content filtering to prevent users from accessing malicious Office documents. Additional protective measures include disabling automatic execution of macros, implementing application control policies, and maintaining regular security awareness training for employees. Network segmentation and monitoring for suspicious file access patterns can help detect potential exploitation attempts. The layered defense approach combining technical controls with user education provides the most effective protection against these sophisticated attack vectors that continue to evolve as attackers develop new techniques to bypass existing security measures.