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What should IT teams patch first on Microsoft Patch Tuesday (February 2026)?
Microsoft’s February 2026 Patch Tuesday includes cumulative updates for supported Windows client and server releases, published under “February 10, 2026” KB articles.
These cumulative updates roll up security fixes (and other quality improvements) into a single monthly package, which simplifies deployment but makes timely testing important.
What the risk looks like
Independent advisories for this release warn that the most severe issues can enable remote code execution, which can let an attacker run code with the same rights as the logged-on user.
A third-party breakdown also shows elevation of privilege vulnerabilities as a large share of the month’s fixes, alongside remote code execution, spoofing, information disclosure, denial of service, and security feature bypass issues.
CVE watchlist (use as a triage starting point)
Treat this list as a routing list for validation, not as final scope, because product impact and exploit status should be confirmed in Microsoft’s advisories before setting urgency.
- CVE-2026-21510: Security feature bypass (Windows Shell / warning prompts); Focus: reduce user-click exposure, block risky shortcut/link patterns, patch endpoints quickly.
- CVE-2026-21533: Elevation of privilege (Remote Desktop Services); Focus: patch RDS hosts, review local admin paths, monitor for privilege escalation indicators.
- CVE-2026-21519: Elevation of privilege (Desktop Window Manager); Focus: prioritize shared workstations and high-risk user fleets.
- CVE-2026-21514: Security feature bypass (Microsoft Word); Focus: tighten file handling, review attachment controls, patch Office quickly.
- CVE-2026-21525: Denial of service (Remote Access Connection Manager / RasMan); Focus: patch remote access endpoints and watch for service instability.
- CVE-2026-21513: Security feature bypass (MSHTML); Focus: restrict untrusted HTML handling paths, patch endpoints, reinforce attachment/link filtering.
- CVE-2026-21511: Spoofing (Microsoft Outlook); Focus: patch Outlook clients, review email threat controls, increase user reporting for suspicious messages.
Also flagged in several briefings:
- CVE-2026-20841: Notepad RCE scenario tied to link/protocol handling in content workflows; Focus: reduce untrusted content opening, patch quickly, review protocol handler policies.
- CVE-2026-21244, CVE-2026-21248: Hyper-V local code execution paths; Focus: prioritize virtualization hosts and developer/test machines that run untrusted code.
- GitHub Copilot CVEs (e.g., CVE-2026-21516, CVE-2026-21523, CVE-2026-21256): Command injection / remote execution themes; Focus: patch IDE extensions and agents, restrict network egress where feasible, monitor developer endpoints.
Deployment checklist (practical and fast)
- Inventory first: List Windows versions, Office builds, RDS roles, Hyper-V hosts, and developer endpoints; map each to the relevant February 2026 KB/update channel.
- Patch by exposure: Internet-facing and remote-access systems first (RDS, VPN/remote tooling), then email and Office-heavy users, then the wider endpoint fleet.
- Reduce “user-click” risk while rolling out: Enforce attachment/link controls, block high-risk file types from email where possible, and tighten application reputation / SmartScreen-related policies.
- Verify after install: Confirm update installation success, check event logs for exploit-like activity, and validate that critical business apps still work (RDS sign-in, Office add-ins, line-of-business apps).