Microsoft Cloud Is Not Secure by Default – Here’s What That Means for Your Business
If your business runs on Microsoft 365, there’s a good chance you assume Microsoft is handling your security. They built the platform, they run the servers, they patch the software. So it should be secure, right?
Not exactly.
What just happened
Microsoft just patched a maximum-severity vulnerability in Entra ID – the system that controls who can log into your Microsoft 365 environment. This is the front door to your email, your files, your SharePoint, your Teams. Everything your business touches in Microsoft 365 goes through it.
The flaw allowed attackers with no existing access to execute code remotely. And it wasn’t theoretical – it was already being exploited in real attacks before the patch was released.
That same week, Microsoft patched four more maximum-severity flaws across Azure and Exchange Online. Five critical vulnerabilities in a single week, all in cloud services that millions of businesses rely on every day.
Why default settings aren’t enough
Most small businesses set up Microsoft 365, turn on email, maybe enable a few basic security settings, and move on. That’s understandable – there’s a business to run.
But Microsoft operates on a shared responsibility model. They secure the platform itself – the data centers, the infrastructure, the underlying code. Securing your specific environment – who has access, what’s being monitored, how sign-ins are handled, whether former employees still have active accounts – that’s on you.
The default security settings in Microsoft 365 cover the basics, but they leave significant gaps. They don’t monitor your accounts for suspicious activity in real time. They don’t alert you when someone logs in from an unusual location at 3 AM. They don’t catch a compromised account before the damage is done.
What layered protection actually looks like
This is where third-party security tools and active monitoring come in. Instead of relying solely on what Microsoft provides out of the box, a properly secured environment adds layers on top:
Continuous monitoring that watches sign-in patterns, flags anomalies, and alerts on suspicious behavior before it escalates. Endpoint protection on every device that connects to your environment – not just basic antivirus, but tools that detect and respond to threats in real time. Regular reviews of your Microsoft 365 security settings to close gaps like unenforced MFA, overshared files, and inactive accounts that still have full access.
None of this is exotic or enterprise-only. It’s practical, affordable, and increasingly necessary for businesses of any size.
The bottom line
Trusting Microsoft to handle everything is a common assumption, and an understandable one. But the reality is that their platform security and your environment security are two different things. When five max-severity vulnerabilities get patched in a single week – and at least one was already being exploited – it’s a reminder that default settings alone aren’t a strategy.
If your business runs on Microsoft 365 and your security setup hasn’t been reviewed recently, it’s worth knowing where things stand.
IMM Computer Services helps Ottawa small businesses get more out of Microsoft 365 – with proper security, active monitoring, and layered protection built for how threats actually work today. Schedule a free consultation to find out where your environment stands.