Article Insights
- Microsoft 365’s popularity makes it a prime target for phishing, ransomware, and email-based attacks, particularly through OneDrive, SharePoint, and Teams.
- Attackers increasingly rely on email and social engineering to gain account access and spread across connected Microsoft 365 apps.
- Built-in tools like Advanced Threat Protection and Multi-Factor Authentication are valuable but are insufficient without stronger, layered defenses.
- Continuous monitoring, correct configuration, and employee training are essential for closing security gaps.
- Partnering with an MSP like Mirazon enhances Microsoft 365 protection through advanced filtering, endpoint security, and active threat response.
- Real-world use cases show how Mirazon’s approach could prevent breaches in industries like healthcare, legal, and SaaS.
- Businesses that go beyond default settings and invest in managed IT services achieve more resilient, long-term Microsoft 365 security.
Microsoft 365 Email: The Security Threat You Can’t Ignore
Microsoft 365 is the productivity backbone of nearly every organization. This comprehensive suite of apps powers your email, document sharing, collaboration, meetings, and more. But what many don’t realize is that this same ecosystem is also one of the most targeted platforms for cybercriminals, and email security is their bullseye.
Phishing scams, malware, and ransomware attacks via emails are increasingly common. Microsoft 365 users are caught in this crossfire. In fact, research by Security Today shows that malware represents 65% of all cyberattacks in M365 apps, including OneDrive, SharePoint, and Teams. [Source]
Attackers follow the data — and in most organizations, that means sensitive client information, financial records, login credentials, and proprietary documents stored in email attachments, cloud file shares, meetings, and group chats. Securing your Microsoft 365 platform is one of the smartest ways to protect your business and ensure long-term productivity.
Let’s break down how these attacks happen, what built-in protections Microsoft offers, and why partnering with a Managed Services Provider (MSP) like Mirazon providesthe extra layer of protection your business needs.
Email: The #1 Attack Vector for Microsoft 365
Despite this shift to video calls and messaging services, employees still rely primarily on email to stay in touch.. And email attacks in Microsoft 365 are cybercriminals’ low hanging fruit.
Cybercriminals use email because it works. The phishing scammer can easily dupe even an experienced employee with a well-composed phishing email and a compelling attachment. The scam targets human behavior– not just a weakness in technology.
Once an attacker gains access to one account, they can pivot quickly, impersonating users, launching internal phishing attempts, or planting malware that spreads through your file sharing platforms.
The common tactics include:
- Phishing campaigns that mimic Microsoft or other trusted vendors to steal login information.
- Malicious attachments disguised as invoices, resumes, or spreadsheets.
- Business Email Compromise (BEC) scams in which attackers take over a legitimate message chain to demand wire transfers or sensitive information.
- Social engineering email attacks that pressure employees to act quickly (“Your account will be disabled unless.”).
This behavior is not a threat to big businesses only. Small and medium-sized businesses are increasingly targeted, partly because their security is more easily breached. Find tips to safeguard your email security here.
Understanding Risks in Microsoft 365 Apps
Email may be the entry point, but the real danger comes after. Once in your network, malware can spread through Microsoft 365’s native features, and even hide in plain sight in places like:
- OneDrive, iwhere infected files are capable of syncing between a user’s devices, like laptops andr personal mobile phones.
- SharePoint, where shared folders canspread malicious documents within a company.
- Teams, where links or attachments can appear in channels and/or chat sessions to release malware payloads.
So, how are these platforms so susceptible to attack? The reason is that they make sharing easy, but without proper configuration and monitoring, they provide openings for attackers.. They get in through lax sharing settings and missing endpoint security. This is why having strong Microsoft 365 SharePoint security and understanding Microsoft 365 Teams security risks are so important.
Hybrid and remote work environments add to this risk as employees are working with sensitive information outside of their organization’s network and often use unmanaged devices. Implementing endpoint security solutions helps protect users in hybrid setups while providing malware protection and ongoing M365 security monitoring for anomalies.
Microsoft 365 Microsoft 365 Does Have Security Features — But They’re Not Plug-and-Play
Microsoft 365 has many advanced security features. However, many of these are either not used extensively enough, or are not configured properly. Too often, they aren’t even turned on. Business leaders often assume that Microsoft 365 is “secure out of the box” when that is simply not the case.
Here’s what Microsoft offers
- Microsoft Defender for Office 365 (formerly Advanced Threat Protection): Scan attachments and links for malware, phishing attempts, and known exploits.
- Multi-Factor Authentication (MFA): Block unauthorized access even if a password is compromised.
- Data Loss Prevention (DLP): Flag and prevent the sharing of sensitive data like credit card numbers or health records.
- Conditional Access Policies: Control access based on device health, location, or risk level.
- Endpoint Management Tools: Monitor and secure devices that access your Microsoft 365 environment.
These features are robust, but won’t provide much benefit unless they’re configured intentionally, monitored continuously, and supported with real user awareness. Knowing how to secure Microsoft 365 applications properly is often the difference between safety and exposure
That’s where a Managed Services Provider (MSP) like Mirazon comes in.
The Missing Piece is Provided through Managed Services: Proactive Protection
We don’t just plug in tools and call it a day. We partner with you to build a security strategy that evolves alongside your business — and the threat landscape.
With Mirazon’s managed IT services, you get:
- Advanced Email Filtering – We deploy multi-layered filters and m365 phishing protection to prevent spam messages, malware signatures, spoofed domains, and malicious file types reaching you even before they land in your mailbox.
- Real-Time Monitoring & Response – We monitor for unusual traffic 24/7. That includes login activity from unknown IP addresses, credential stuffing attacks, and signs of compromised accounts. We act immediately when we detect a threat.
- Correct Configuration of Microsoft 365 Security Features – We ensure that security features like Defender, MFA, and DLP are configured to address your business requirements rather than simply turned on and left to their default settings.
- Endpoint Protection – Managed antivirus software, encryption capabilities, and mobile device management andsecure access tools ensure that your data is protected regardless of where your employees are working.
- End-User Training and Support – The strongest tools cannotcompensate for human error. That’s where employee training comes in to recognize and immediately report phishing.
Learn about Mirazon Managed Services
Examples of Where Managed M365 Security Makes a Difference
Security isn’t just about theory, it’s about real outcomes. Here are a few examples of how Mirazon can help clients improve their Microsoft 365 defenses and avoid serious threats:
When Managed Security Stops an Attack in Its Tracks
A finance manager receives a SharePoint file that looks like a routine invoice. But something’s off – the sender is spoofed, and the file includes a malicious macro. Thanks to Mirazon’s day-to-day monitoring and finely tuned Advanced Threat Protection policies, the threat is quarantined before the user ever clicks. No downtime. No lost data. Just proof that managed security catches what default settings miss.
How a Healthcare Provider Could Avoid a Ransomware Lockout
Imagine a regional medical clinic being targeted by a phishing campaign. An attacker sends a convincing email with a malicious Excel file attachment. Without proper filtering, it could easily slip through to an unsuspecting staff member. But Mirazon’s ransomware protection for M365 and managed security approach, layered filtering would block the payload before it ever reaches the inbox. And if something suspicious does make it through, endpoint detection and offsite backups would help the clinic stay operational, avoiding data loss, downtime, and what might otherwise be a six-figure recovery effort.
How a Remote Startup Could Secure SharePoint and Teams
Picture a fully remote SaaS startup unknowingly exposing sensitive folders via SharePoint, which is a common oversight in fast-moving environments. With a Mirazon-led Microsoft 365 security assessment, the company could identify and correct misconfigured permissions, lock down public access points, and implement endpoint security across employee laptops. That way, they’d not only reduce their immediate risk, they’d also build a scalable Microsoft 365 security foundation for future growth.
So whether it’s stopping ransomware before it spreads, tightening up access controls, or guiding your remote workforce through secure collaboration, Mirazon’s proactive managed services for Microsoft can make all the difference.
How to Secure Microsoft 365 Right Now
If you’re wondering where to start, here’s a practical checklist to level up your Microsoft 365 email security. These aren’t just best practices, they’re critical safeguards that help reduce your exposure to phishing, ransomware, and data loss.
Whether you’re a small business or an enterprise IT team, addressing these areas will drastically improve your defense against modern cyberattacks.
- Enable multi-factor authentication for Microsoft accounts using phishing-resistant methods
- Harden Microsoft Defender for Office 365 and Advanced Threat Protection policies
- Configure SPF, DKIM, and DMARC to validate email authenticity
- Review data loss prevention rules and backup/recovery plans regularly
- Adopt a Zero Trust framework to limit exposure
- Partner with a managed IT provider who can provide continous monitoring and response
- Train your team regularly to spot phishing and social engineering attacks
Build a Safer, Smarter Microsoft 365 Environment
The threats to Microsoft 365, especially those that arrive through emails, are real and constantly changing…looking for opportunities to strike. No organization is too small to be targeted.
Just relying on default settings and/or updating manually is no longer good enough. You need a strategy. You need resources. You need visibility. You need managed IT services for Microsoft 365.
No matter your industry, size, or specific security challenge, Mirazon brings the expertise, tools, and industry-specific knowledge to help secure your Microsoft 365 environment.
Protect your Microsoft 365 environment from AI-driven phishing and ransomware. Contact Mirazon’s Managed Services team to strengthen your email security, harden configurations, and safeguard your users from modern cyberattacks.