AISEC > Security News > Zero Day > Microsoft Patch Tuesday February 2026: 6 Zero-Days Exploited
February 10, 2026 #zero-day Source: Krebs on Security 3 min read · 636 words

Patch Tuesday, February 2026 Edition

Patch Tuesday, лютий 2026 року

Microsoft's February 2026 Patch Tuesday: Six Zero-Days Already Under Attack

Over 50 security vulnerabilities. Six of them zero-days actively being exploited right now. This isn't theoretical risk—attackers are already weaponizing these flaws.

According to Krebs on Security, Microsoft's February 2026 Patch Tuesday brought a heavier-than-usual load of critical fixes, and the presence of half a dozen zero-day vulnerabilities that were already in the wild makes this one of those updates you don't want to sleep on.

Breaking It Down

So let's be clear about what we're dealing with here. Six zero-days means six security holes that Microsoft didn't know about until attackers started actively using them. There's no grace period. There's no "we'll patch this next month." Once a zero-day goes public—or worse, gets exploited—the clock starts ticking immediately.

The full vulnerability patch Tuesday list includes patches across Windows and various other Microsoft software. This is particularly nasty because the attack window was already open. Attackers weren't waiting for a patch announcement; they were already inside systems, exploiting these flaws for days or weeks.

And then it got worse.

Windows vulnerability research over the past year has shown an uptick in zero-day usage. We're seeing attackers shift away from relying on known exploits and toward targeting unpatched flaws they discover themselves. This February patch Tuesday validates what security researchers have been warning about: zero-days aren't rare anymore—they're becoming routine.

The Technical Side

Here's where it matters. A zero-day vulnerability is a flaw in code that nobody's publicly disclosed yet. The developers don't know about it. The security community doesn't know about it. Only the attackers know about it—and they're using it.

Windows vulnerability management becomes exponentially harder when you're dealing with unknowns. Traditional detection methods rely on signatures and known attack patterns. With zero-days, there's no signature. There's no pattern history. The only way you catch these attacks is through behavioral monitoring—looking for weird activity rather than known bad activity.

What makes vulnerability patching critical in cases like this is speed. Once Microsoft identifies a zero-day and releases a patch, the window of opportunity for attackers shrinks rapidly—but only for organizations that actually apply the patches. Anyone still running unpatched systems becomes a sitting duck.

Who's Affected

This one's simple: Windows users everywhere.

If you're running Windows—any version that Microsoft still supports—you need to assume your systems could've been targeted. The fact that these zero-days were actively exploited means attackers have already compromised some number of machines. Your organization might be among them without knowing it yet.

Enterprise environments are particularly at risk because patching at scale takes time. A company with 10,000 machines can't just flip a switch and update everything in five minutes. That gap between patch release and full deployment? That's where attackers live.

What To Do Now

First, stop reading and start patching. Not tomorrow. Not "during the next maintenance window." The zero-days are already being exploited, which means every hour you delay is an hour attackers have access to known vulnerabilities on your systems.

If you're managing a Windows vulnerability scanner in your environment, run it today. Get a baseline of which machines are vulnerable and prioritize critical systems first—domain controllers, email servers, internet-facing applications.

Second, implement a Windows vulnerability management strategy if you don't already have one. Monthly Patch Tuesday updates aren't optional anymore. They're table stakes.

Finally, assume breach. Even after you patch, run detection queries looking for signs that these zero-days were exploited in your environment. Look for unusual network connections, unexpected process execution, or suspicious account activity dating back to before the patch release.

This is exactly why the security community keeps hammering on patching. It's not sexy. It's not exciting. But it's the difference between "we got hit but we patched quick" and "we got hit and we didn't even know about it for six months."

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// FAQ

Do I need to apply the February 2026 Patch Tuesday update immediately?

Yes. Since 6 of the 50+ vulnerabilities were zero-days actively being exploited, Microsoft recommends immediate deployment. Organizations should prioritize critical systems and deploy within 24-48 hours of assessment.

How do I check if my Windows system was compromised by the zero-day exploits?

Run a Windows vulnerability scanner to check patch status, then review system logs and network traffic for suspicious activity dating back several weeks. Consider deploying endpoint detection and response (EDR) tools to identify behavioral anomalies from exploitation attempts.

What should I do if patching all my Windows machines takes more than a few days?

Prioritize internet-facing systems, domain controllers, and servers first. Isolate or closely monitor unpatched machines in the interim, and implement network segmentation to limit lateral movement if compromise is detected.

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