@inversecos

If an attacker gains access to an Azure tenant (with sufficient permissions) they can add a “secret” or a “certificate” to an application. This will allow an attacker single-factor access to Azure allowing the attacker to persist within the client environment. Further, each application that exists within an Azure tenant has a service principal automatically assigned/created. This happens every time an application is registered within an Azure portal. A service principal account is basically an identity that’s used by applications, tools to access resources / perform automated actions.   Attackers want to target service principals because: Service accounts and service principals do not have MFA Attackers can log into Azure using a service principal account These accounts exist with all applications in Azure (most companies have several)  These accounts cannot be controlled through conditional access This blog post is going to show you how to create / register an applicatio...

In my previous blog post, I detailed an attack matrix for Microsoft 365 (M365), documenting the various attacks and actions on objectives that can be taken by threat actors. My original matrix did not touch on some other hybrid attacks that can happen on Azure AD which are relevant to the Microsoft Cloud environment. As such, I have modified and updated the attack matrix below to show all the various attacks collated into one matrix. For those of you who are not familiar with M365 or Azure AD (AAD), the reason I built this matrix is because the Mitre O365 matrix did not include a comprehensive list of all the various attack vectors. To be a good responder / defender, it’s important to understand the different types of attacks that your organisation or client may be plagued with. Attacks on Azure AD and M365 are not limited to simple business email compromise cases (BECs) but are now actively being exploited by nation-state APT groups. The reason that these actors choose the cloud as ...

APTs are actively attacking Office 365 (O365) – finding mechanisms to bypass MFA and to impersonate users regardless of whether you reset their passwords. When I was looking through the Mitre mapping of O365 attacks , I noticed that it didn’t include many methods of intrusion and actions on objectives that can occur with O365. In conversations with several clients, I couldn’t help but notice that there’s still a heavy focus on “endpoint” style attacks and not much resource / thought put into attacks that can occur in the cloud. Attacking O365 gives an attacker many benefits… it allows an attacker to impersonate users, alter MFA settings, register malicious devices, access Teams messages, download sensitive emails, access SharePoint, OneDrive, register malicious applications and various other actions that could allow them to maintain persistence in your environment. This blog post explores the various ways O365 can be attacked. I will be writing a Part II follow up that describes the me...