O365 security

5 Ways to Secure Your Microsoft 365 Today

For many businesses, Microsoft 365 is an essential part of performing daily business tasks and transactions. The office suite software is used by over a million companies worldwide. With convenient cloud storage and easily accessible tools, it's no surprise that the platform rose in popularity as a powerful assistant to practically any business. When companies were suddenly launched into remote work due to pandemic restrictions, the Microsoft platform became an indispensable tool for remote workers. Unfortunately, the pandemic also presented an opportunity for hackers to target more widely used organizations like Microsoft 365 to breach business networks. 

In 2021 alone, tens of thousands of organizations had the security of their Microsoft 365 systems compromised through the use of various Microsoft Exchange vulnerabilities as a gateway. The earliest attacks occurred in January and the Exchange server exploitation escalated to a global scale by the end of February. Microsoft released a patch on March 2. The following day CISA released an emergency directive to all federal government agencies. Despite the continued criminal activities targeting the Microsoft 365 vulnerability, many companies failed to patch their systems. As awareness of this mass exploitation and other Microsoft 365 vulnerabilities came to light, organizations began to question their vulnerability in relation to the platform. 

There's no doubt that systems without crucial security patches are still exposed to known vulnerabilities. Yet, there's also no guarantee that patched networks are completely free from security vulnerabilities. While it's true that the Microsoft office suite offers a multitude of effective security features, many businesses don't fully understand how to use them. A network with strong security features that go unused is like a home with a lock you forget to engage. To better protect your network, it's essential to get familiar with the reasons that Microsoft 365 could make your network vulnerable, and how you can take action right away to improve your office security posture.

Free Download: Office 365 Mail Filtering Best Practices

Why Microsoft Office 365 Could Make Your Network Vulnerable to Cyberattacks

Microsoft 365 is a popular office suite that provides businesses across multiple industries with critical tools to keep things running. The platform is widely adopted for a variety of reasons. However, its popularity also makes it attractive to hackers as well. For organizations that depend on the office suite, it can be difficult to understand if your use of Microsoft 365 is putting you at risk. The truth is, there are some reasons that Microsoft 365 could expose your organization to cybersecurity vulnerabilities.

Microsoft 365 is a Platform Used by Millions of Businesses

When it comes to office suites, there is no bigger name than Microsoft Office. In the US business world, Microsoft 365 has a 47.6% market share. While this makes it an obvious choice for businesses that need to work seamlessly with enterprises that use the office suite, it also makes it an attractive target for criminals. A vulnerability in a single network provides threat actors with access to the data owned by a single organization. On the other hand, a vulnerability exposed within the office suite used by nearly half of US businesses offers the potential to access millions of networks the same way.

When vulnerabilities are exposed, a new layer of threats is revealed. Cybercrime as a service describes a business model in which threat actors rent or sell cybercrime "solutions" to other criminals. When an exposed vulnerability becomes public, businesses using the platform are exposed to increased risk by low-level hackers that don't need the knowledge or experience to conduct cyberattacks. In other words, the number of attacks increases rapidly simply because more criminals have access to the technology to commit cybercrime than ever before.

Microsoft 365 Apps Are Designed to Perform Sensitive Activities

Microsoft 365 has it all. Business tools for collaboration, data storage, business email, document management and sharing, etc., is what the platform is known for. It's all the activities that keep businesses running efficiently, and all the natural targets for cybercrime. Consider how some of Microsoft 365's most popular platforms make a natural target for cybercriminals as well.

Outlook 365/Business Email

As one of the most effective ways for businesses to communicate globally, email offers hackers a way to exploit human errors. 85% of breaches include a human element and 61% are related to stolen or misused credentials. This makes email the perfect vector for some of the widely used attacks, including phishing, spam, credential theft, ransomware delivery, social engineering attacks, and business email compromise.


Cloud-based storage is convenient and ideal for the scalability needed for growing and changing businesses. For cybercriminals, storage always has the potential to harbor sensitive data. Companies that depend on legacy security systems might not have adequate security for cloud storage, making cloud storage the perfect vulnerable target.


One of the biggest selling points of SaaS for businesses is the convenience of essential tasks like sharing documents. Yet interception attacks like account takeover, credential theft, or phishing can make document sharing a potential vulnerability. Although it's important for businesses to easily share data inside and outside an organization, the same tools can be targeted by unauthorized parties attempting to steal data.


Now, more than ever, team members need tools that allow them to collaborate from wherever they are. Yet, correspondence tools potentially can allow threat actors to "eavesdrop" on companies to gain access to sensitive information or advance permissions within a network. 

The reality is, Microsoft 365 provides a wide range of products that offer different attack vectors for cybercriminals to exploit. While the cloud platform isn't inherently vulnerable to cyberattacks, it provides a variety of attractive tools and various modes of attack for cybercriminals to exploit.

Legacy Security Systems Might Fail to Adequately Protect Cloud Platforms

Cloud platforms offer a host of benefits for businesses. With no internal infrastructure to maintain, these platforms are typically cheaper. They offer scalability for growing storage needs, offer more flexibility, and improved customer service. However, many organizations don't recognize the security needs of cloud platforms. 

When organizations have depended on a seemingly successful in-house security solution for decades, it's easy to assume there's no reason to fix something that isn't broken. However, older systems are often not equipped to handle the security needs of cloud platforms. Whether attackers have inside knowledge about such systems or work on the expectation they exist, targeting cloud platforms offers the potential to find inadequately protected networks.

All Apps and Platforms Are Subject to Human Error

Many of the most frequently used cyberattacks don't target system vulnerabilities. They target humans that are capable of overriding systems with effective security measures in place. For example, phishing and BEC attacks focus on tricking an authorized user to provide an entryway into the network or to unknowingly commit a crime.

Since Microsoft 365 is used by the majority of businesses and utilizes tools that allow businesses to perform critical tasks that include communications, data management, and document sharing, it's a natural target. The only way to protect any platform from the dangers of human error is to educate network users about the dangers that exist.

Microsoft 365 Default Settings Are Optimized for Convenience Instead of Security

Microsoft 365 is a production suite designed to help streamline business tasks and improve the way companies communicate with vendors, customers, and other businesses. The company takes data protection seriously and includes a range of robust security capabilities to help companies protect critical data. However, businesses always must strike an agreeable balance between the productivity that makes a business successful and the level of security that prevents expensive attacks. In other words, your security features shouldn't be so cumbersome that they inhibit productivity.

Every organization is different, with varying levels of sensitive data and critical processes. Microsoft provides security tools with options that allow organizational leaders to choose the level of security practices that best meets their needs. Unfortunately, many companies aren't familiar with out-of-the-box security defaults or the vulnerabilities they could present. As a result, the Cybersecurity & Infrastructure Security Agency (CISA) released a report in 2019 to address defaults that could represent configuration vulnerabilities. By being cautious, companies can avoid potential vulnerabilities. However, companies that fail to make changes could be making themselves a target.

How Do I Know If My Office 365 Is Secure?

The conversation surrounding Microsoft 365 can make it difficult to understand exactly how your use of the platform affects your security. The truth is, Microsoft Office 365 has the capability to be a very secure platform for business use. However, organizations must take steps to assess their vulnerability and close security gaps. Take these steps to determine if your Office 365 is secure.

Check Your Secure Score

Microsoft Secure Score is a measurement of an organization's security posture within the office suite. It provides you with a report on your current O365 security posture, recommended steps to improve your security, and benchmarks for comparison. Your organization's unique score is calculated based on security-related actions like system configurations and user behavior within Microsoft 365 tenants.

The Microsoft Secure Score is free to use and can be found in the Microsoft 365 Devender portal. On the Secure Score Overview Page, you can see the score that represents your current security status and the actions you can take to improve your score.

Learn the Signs of a Compromised Account

If your Office 365 has already been breached, it's crucial to take steps to determine where the threat exists and conduct appropriate response actions to limit potential damage to your network. Microsoft identifies these symptoms as a possibility your account has been compromised.

      • The Sent or Deleted items folders in Outlook or Outlook Web App contain common hacked-account messages.
      • Unusual profile change updates like a phone number or postal code changes have occurred.
      • Multiple password changes are required.
      • Mail forwarding was recently added.
      • An unusual signature was recently added.
      • Missing or deleted emails are observed.
      • A user's mailbox is blocked from sending an email.

Conduct a Third-Party Security Gap Assessment

For most companies that depend on cloud platforms for business tasks, cloud-based security services from a managed service security provider (MSSP) are a critical part of comprehensive security. A highly qualified MSSP will begin by assessing your security needs based on all the services, platforms, and applications you depend on. This analysis will illuminate existing security gaps created by Microsoft 365 and other platforms in your environment.

Free Download: Office 365 Mail Filtering Best Practices

5 Ways to Improve Your Microsoft Office 365 Security Today

There are countless ways businesses and organizations can improve their cybersecurity posture. However, most of them take research and time. It's true that Microsoft 365 has a plethora of built-in security features. Yet, it's very likely that your organization isn't using them all in the way that offers the most protection. How your organization uses Microsoft 365 apps and services is pivotal to keeping your data safe. These 5 tips can help you improve your Microsoft Office 365 security right away. Educate Employees

Activate Security Settings

Leaving any platform or device's settings on default can lead to network vulnerabilities. In many cases, the software is designed for a simple setup and quick time to value. However, these settings should often be changed after setup for adequate password difficulty, security protocols, etc. One of the fastest ways to make your Microsoft 365 accounts more secure is to make changes to these default settings.

Secure O365 Email

By changing certain defaults within the platform, you can make Office 365 email more secure. Begin by requiring multi-factor login for all users. Change the defaults within email accounts to disable auto-forwarding of emails, configure anti-phishing protection, and encrypt sensitive messages. If you're using a legacy O365 account (from before 2019), you'll also need to enable the email audit log and unified audit log to easily detect internal threats.

Enable Multi-Factor Authentication (MFA) for All Accounts

This can be completed by company leaders or users can enable MFA themselves.

Block Guest Invite Access

Users can invite guests to collaborate on Word documents or other resources. This may be necessary for certain projects, However, by default, these guests can also invite other guests. To change this capability, go to External Identities in the Azure Active Directory, select External Collaboration Settings, and make sure Guests Can Invite is set to no. 

Limit External Sharing in SharePoint

Document sharing is a convenient business capability that can streamline tasks. However, it's essential to ensure that mistakes don't allow other parties to view sensitive data. By requiring the receiving party to sign in or enter a verification code, you can ensure your documents are only seen by the people you intend to share them with. To limit sharing, open the SharePoint Admin Center, choose Policies, and then Sharing. Change Content can be shared to new and existing guests. Expand More External Sharing settings. Enable Guest Must Sign in Using the Same Account.

Protect Against Ransomware

Malware is often delivered through file delivery systems or attachments that are frequently used for general business tasks. By defining a chosen system for delivering files and sharing documents, you can decrease the chances of an accidental malware download.  After creating such a policy, you can use Microsoft 365 to automatically block file types or attachments that cybercriminals commonly use for malware.

Reduce Permissions

It can be convenient to allow all users unlimited access to critical information. When access is needed employees can skip added steps to complete tasks. However, high access levels for multiple users is a critical security vulnerability. Instead, access to sensitive information should be based on the principle of least privilege. In other words, user accounts should always have the minimum privilege level that is needed to do their job. 

Limit permission by creating dedicated admin accounts for specific privileged users. Equip admin accounts with multi-factor authentication, and limit these accounts to as few as possible. Set up a separate user account for non-administrative tasks so admins only use admin accounts when necessary. This makes suspicious use of an administrative account easier to spot and less likely to occur.

Immediately Apply Updates and Patches

When security vulnerabilities are exposed, software developers immediately create patches or updates to address the security issue. Typically, a patch may be created as soon as a single company reports a breach due to a security gap. Unfortunately, many organizations fail to immediately implement patches which puts them at a much higher breach risk. 

Exposed vulnerabilities are a known threat to businesses and organizations. This means they're also known to threaten actors intent on using these security gaps while they're available. Failure to implement patches is essentially the same as leaving an entryway open for hackers to exploit at will.

Enable Unified Audit Logs

Taking every precaution to prevent unauthorized access to Office 365 and all platforms within your network is a necessary part of effective security. However, it's also vital to plan ahead in case your network experiences a breach. Modern sophisticated attacks are usually carried out in multiple steps that allow attackers to discreetly investigate your network and obtain essential permissions to carry out a large-scale attack. When a breach occurs, there could be essential information available within your network to identify the attacker and respond before the objective is reached. 

Audit logs provide visibility into your network and allow security analysts to investigate vulnerabilities before critical damage occurs within your network. Office 365 audit logs are found in the Office 365 Security & Compliance Center. However, logging capabilities are not turned on by default, and the retention period of these logs may not be sufficient. To enable log monitoring, log into the Security & Compliance Center of your account and select Audit. If auditing is not turned on for your organization, a banner is displayed prompting you to start recording user and admin activity. Click the banner to turn on log auditing. 

For the Most Comprehensive Microsoft Office 365 Security Invest in Multi-Layer Security From MSSP

The modern enterprise depends on cloud platforms, third-party connections, remote devices, and a variety of applications to seamlessly and efficiently keep business running. To effectively protect all extensions of your business network, it's essential to invest in complete end-to-end security with management from trained and experienced cybersecurity professionals. 

While Microsoft offers critical security tools to help businesses add an essential layer of protection to their networks, complete unified visibility of all activities is the most comprehensive security tool available to help you identify and respond to cyberattacks. Microsoft follows the shared responsibility model where Microsoft assumes the responsibility of application availability and the security tools to protect data used within their system. However, the customer is responsible for administration and user management that keeps your sensitive data secure within the platform.

At BitLyft, it's our mission to build a safer cyber landscape that allows businesses to use the modern tools and technology necessary to run a modern enterprise. We provide unparalleled protection for organizations of all sizes by delivering the best people and software to remediate most cyberthreats in seconds. To provide the most comprehensive visibility into the activities that take place within your Microsoft 365 tenants, our experienced teams leverage Securonix Next-Gen SIEM to monitor all aspects of the cloud and streamline remediation of email-borne threats before a loss occurs. Through integrations with Microsoft 365, SharePoint Online, Exchange Online, and Azure AD, Securonix leverages Microsoft's security infrastructure to collect all threat information into a single source of truth.

No matter what platforms and applications you depend on to keep your business running, your security solution should be tailored to your unique needs. Schedule a 30-minute needs assessment with BitLyft to get a better understanding of the ways you can better protect your organization against sophisticated cyber attacks.

Free Download: Office 365 Mail Filtering Best Practices

More Reading

Stolen credit cards from phishing email
How to prevent the top five social engineering attacks
As more and more high-profile cyberattacks become headline news, businesses across all industries are becoming aware that effective cybersecurity is a necessary part of business operations. Network...
Vulnerability Scanning
Vulnerability Scanning: Here's Everything You Should Know
Hackers work hard. A well-protected organizational network has defenses to protect all endpoints, infrastructure, and devices. Yet, cyberattackers work tirelessly to find flaws in software or...
O365 Security
Improve Microsoft Office 365 Security with a Vulnerability Assessment
If you rely on Microsoft Office 365 for the many tasks your company needs to complete each day, you're not alone. Over a million companies worldwide depend on office suite software. The fact that so...