The December 2025 Security Update Review highlights critical vulnerabilities addressed across various vendors, with a significant focus on Microsoft’s Patch Tuesday. This monthly analysis by the Zero Day Initiative (ZDI) details the disclosed security flaws and the vendor responses, providing essential insights for cybersecurity professionals.

Key Vulnerabilities Patched in December 2025

Microsoft’s December 2025 Patch Tuesday included patches for numerous vulnerabilities, some of which were discovered and disclosed by ZDI researchers. These updates are crucial for maintaining the integrity and security of systems globally. The ZDI review specifically tracks the status of their disclosed bugs, including those that were fixed as part of this update cycle.

The analysis from ZDI covers specific details of the vulnerabilities, often including their type and potential impact. For instance, the December 2025 updates addressed issues ranging from remote code execution to elevation of privilege vulnerabilities, impacting various components of Microsoft’s ecosystem. The prompt patching of these flaws is a testament to ongoing efforts to secure digital infrastructure.

Zero Day Initiative’s Contributions to Security

The Zero Day Initiative plays a pivotal role in identifying and responsibly disclosing vulnerabilities to vendors before they can be widely exploited. Their December 2025 review serves as an important resource, chronicling their contributions to the month’s security updates. ZDI’s work often results in patches that protect millions of users and systems from potential cyberattacks. This continuous research and disclosure process underpins a proactive approach to cybersecurity, pushing vendors to enhance their product security.

Understanding the details within each monthly security update, as provided by ZDI, enables organizations and individuals to prioritize their patching efforts and strengthen their defenses against emerging threats. The December 2025 review offered a comprehensive look at the vulnerabilities addressed and the diligent work behind their resolution.

Source: https://www.thezdi.com/blog/2025/12/9/the-december-2025-security-update-review