Azure AD Seamless SSO allows enumerating tenant users

Azure AD Seamless SSO allows enumerating tenant users

In 2017, Oliver Morton introduced a feature he found in Office 365 Active Sync, allowing enumerating the existence of the users based on http status codes. (Update: The “feature” was fixed by Microsoft on mid November 2019). In this blog, I’ll introduce my similar findings on using Microsoft API to enumerate users when Seamless SSO is enabled in Azure AD tenant.

Deep-dive to Azure Active Directory Identity Federation

Deep-dive to Azure Active Directory Identity Federation

Identity federation is regarded as the most secure way to authenticate users to Azure AD. In this blog, I’ll deep-dive to identity federation implementation of Azure AD and point out some serious security issues.

How to create over 256 character long passwords for cloud-only users

How to create over 256 character long passwords for cloud-only users

Microsoft (finally!) announced in April 2019 the support for 8-256 character passwords in Azure AD/Office 365. This limit does not apply to users whose passwords are synced from the on-prem Active Directory (or for federated users). In this blog, I tell how to set insanely long passwords (64K+) also for cloud-only users!

How to create a backdoor to Azure AD - part 1: Identity federation

How to create a backdoor to Azure AD - part 1: Identity federation

On November 2018 Azure AD MFA was down over 12 hours preventing users from logging in to Office 365. Same happened in October 2019 in US data centers. As MFA is usually mandatory for administrators by company policy, they couldn’t log in either. In this blog, I’ll show how to create a backdoor to Azure AD so you can log in and bypass MFA.