Microsoft January Patch Tuesday Fixes 114 Vulnerabilities Including Three Zero-Days
Microsoft’s January Patch Tuesday security updates addressed 114 vulnerabilities, including three zero-days reported as publicly known and/or exploited. Reported issues span multiple Windows and Microsoft product components, including Desktop Window Manager (DWM), legacy modem drivers, and core OS services, with a mix of information disclosure, elevation of privilege (EoP), security feature bypass, and remote code execution (RCE) flaws.
Technical highlights called out include CVE-2023-31096 (Windows Agere Soft Modem Driver EoP), CVE-2026-20805 (DWM information disclosure), and a Secure Boot certificate expiration security feature bypass (CVE-2026-21265). The update set also includes multiple Office/Excel/Word RCE vulnerabilities (e.g., CVE-2026-20952, CVE-2026-20953, CVE-2026-20955, CVE-2026-20957, CVE-2026-20944), Windows privilege-escalation issues (e.g., Windows Graphics Component and VBS Enclave EoP), and cloud/agent components such as Azure Connected Machine Agent (CVE-2026-21224) and Azure Core shared client library for Python (CVE-2026-21226).
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