Microsoft Patch Tuesday for December 2025 — Snort rules and prominent vulnerabilities
Summary: Microsoft's December 2025 Patch Tuesday covers 57 vulnerabilities, two of which Microsoft rated "critical" and the rest "important," with exploitation of the two critical flaws assessed as "less likely." The critical entries include CVE-2025-62562, an Outlook remote code execution use-after-free that requires a malicious email and a user reply, and CVE-2025-62456, a heap-based buffer overflow in Windows Resilient File System (ReFS) that allows an authorized attacker to execute code over a network. Cisco Talos released a new Snort rule set to detect attempts to exploit some of these vulnerabilities.
What you should know: Microsoft rated the two critical flaws as less likely to be exploited, but Talos still built detection rules for them and flagged several "important" vulnerabilities that Microsoft lists as more likely to be exploited - a reminder that severity labels and real-world exploitation risk do not line up, and your patching order should follow the latter.
Read the original at Cisco Talos ↗
- Topics
- Vulnerabilities & Patching
- Mentions
- CVE-2025-62456CVE-2025-62549CVE-2025-62553CVE-2025-62554CVE-2025-62556CVE-2025-62557
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