Office 365 is a fantastic resource for the modern company. Our team has a thorough review process to assess all aspects and identify any threats or areas for improvement in your Office365. 

If you have any concerns regarding your O365’s safety from threat actors or other potential issues, our team can help you with your Office 365 security controls.

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Office 365

Office 365 is a powerful tool that provides all sorts of business services from email to cloud storage, and it’s much more than just another productivity suite.

It provides more than just email and office productivity tools – with over 200 million active users worldwide who are constantly growing their products’ capabilities there really isn’t much missing when compared to Microsoft on-premises solutions (such as Exchange Server).

With Office 365, you can get access to an array of tools that will streamline your workflow and give you the freedom to work from anywhere. The security aspect should also not be overlooked though – it’s important in every business!
office 365 security review

Is office 365 email secure?

Whether it’s applications, devices or storage including backups, these are the three main categories where email data resides. Before understanding whether Office 365 is secure or not, it’s important to understand the cloud model concept. Just like major cloud providers, Microsoft offers this product as part of a shared responsibility model in cloud computing. This means:

Cloud provider is responsible for security of the cloud

Tenant or organisation client is responsible for security in the cloud

As customers have control of user accounts, access, authentication and authorisation of O365 data, it is customer’s (tenant organisation) responsibility to maintain the security of their sensitive data. There are good security controls out of the box that come with Office 365, however, they are not auto-magically serving an organisation’s demands.

Common O365 security misconfigurations and vulnerabilities

Our certified security professionals will perform a review of the Office 365 configuration to identify misconfigurations that may have occurred. It is very common for potential threats to be found during this process, and our team will support the mitigation of these threats. Recent bugs i.e. actual vulnerabilities identified within the product had also increased the attack surface for Office 365 users. Some of these recent flaws include improper validation (CVE-2020-16875) and smart bypass issues (CVE-2020-171324). Common Office365 misconfigurations include lack of multi-factor authentication, password sync and mailbox auditing. 

This thorough review includes vendor security best practices including but not limited to the following security review areas:

Benefits of Office 365 Security Assessment

Follow best security practices

Security reviews findings are mostly around areas described under common misconfiguration. As a standard best practice checklist, an Office 365 installation should follow the following areas:

  • Unified Audit Logging
  • Multi-Factor Authentication 
  • Privileged accounts management
  • Protecting against malware using features based on subscriptions such as anti-phishing, auto-forwarding, ATP safe attachments and ATP safe links. 


Microsoft Office 365 provides cloud resources, securing it is your responsibility.

Office365 Security Review Methodology

Our assessment approach involves benchmark based assessments as well as standard pentest methodology extended to include Microsoft cloud specific security concerns. We support industry-leading testing standards and methodologies:

Step 1
Step 1

Identity and Access Management

This phase involves reviewing identity and access management related controls. Generally, these include checks on the use of higher privilege accounts, use of MFA, password policy, IAM policies, access keys and credentials usage policies

Step 2
Step 2

Review Authentication Architectures

Authentication and authorization problems are prevalent security risks. Most mobile apps or azure web applications implement user authentication. Even though part of the authentication and state management logic is performed by the back end service, authentication is such an integral part of most mobile app architectures that understanding its common implementations is important.

Step 3
Step 3

Network Security

This area involves checks around network security controls such as ingress, egress rulesets, flow logging, traffic restrictions, and least access privileges.

Step 4
Step 4

Logging API Calls, Events

All major cloud service providers offer web services that record API calls for tenant account. This information contains various parameters such as API source, calls details, requests/response elements. This phase includes a review of API calls for an account, log file validation, encryption at rest, access checks if logs are restricted from public view and access logging, configuration management and monitoring options.

Step 5
Step 5


The monitoring phase is one of the critical tasks responsible for alerting relevant contacts during an incident. This involves reliance on the logging and related configuration parameters to ensure right metric filters are in place. These reviews include checks for real-time monitoring configuration, alarms for any changes made to access control lists, security policy/groups, routing tables, and related parameters.

Our Cyber Security Testing Services

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