Welcome to the third edition of the “Breaking Down the Breach” series. Today, we’ll discuss a CEO who fell victim to a cyber-attack, highlighting that even the highest-ranking officials are not immune. This series underscores the importance of proactive cybersecurity measures for everyone, regardless of their position.

Please take a moment to read about the unfortunate experience of this CEO, whose Microsoft 365 account was compromised through a phishing attack. Although the attack was quickly remediated, made possible by subscribing to our advanced security services, it serves as a reminder of the ever-present cyber threats.

What Happened
Why It Happened
How It Could Have Been Prevented
Key Insights

What happened

A CEO received what appeared to be a Docusign email asking him to sign a document. It so happens that the CEO was expecting a Docusign email to arrive for a legitimate purpose. With that, his guard was down, and he instinctively clicked on the link. He was directed to a malicious Microsoft 365 login page where he entered his credentials and provided his MFA code, unknowingly giving the attacker access to his Microsoft 365 account.

Our SIEM/SOC solution alerted us to a login from outside the USA. The alert was initially plausible given the company’s global footprint and the CEO’s recent travel overseas. However, we immediately locked down the account upon confirming with our internal contact that the CEO was not traveling.

As part of our standard business email compromise (BEC) protocols, our team forced a sign-out and blocked further sign-in. Despite no alerts from our Endpoint Detection and Response (EDR) or antivirus solutions on the CEO’s devices, we conducted in-depth scans as a precautionary measure, finding no evidence of a lingering foothold.

Fortunately, the CEO had been provisioned two user accounts, one with admin status and a second for daily tasks, the latter of which was compromised. We confirmed his admin account was secure, reset his password, and ran additional scans on his two workstations as part of best practices.

Why it happened

The CEO fell victim to a phishing attack due to a lapse in vigilance, illustrating that even those with security awareness can be targeted. The attack exploited his familiarity with the expected Docusign email, leading to credential compromise.

The SIEM/SOC solution detected the anomaly, but without such a system, the breach might have gone unnoticed, allowing the attacker to maintain access.

How It Could Have Been Prevented


Even CEOs with an understanding of modern security practices are susceptible to targeted attacks. Vigilance is crucial at all levels.


Proactive deployment of Managed Detection and Response (MDR) tools is becoming increasingly important. These tools can detect and isolate threats early, even if additional services are not in place.


Implementing SIEM/SOC solutions, which pull logs from multiple sources and analyze threats collectively, is now more affordable for SMBs. There was a time when they were prohibitively expensive, but advancements and competition have made them much more viable for small businesses.


This incident underscores that multi-factor authentication (MFA) is not foolproof. The phishing attack bypassed MFA, highlighting the need for additional security measures and vigilance.

Key Insights

This incident underscores that multi-factor authentication (MFA) is not foolproof. In the past, having MFA in place was a viable way to exclude yourself from being “low-hanging fruit” and deter most attackers. However, in this case, the attacker easily bypassed it. This highlights the need for more advanced tools and strategies to secure your systems.

The weakest link in your information security chain is often your users. Continuous security awareness training is vital to prevent inadvertent clicks on malicious links or sharing of credentials.

Utilizing advanced detection tools like SIEM/SOC and EDR/MDR solutions is crucial for a robust cybersecurity posture. This attack serves as a stark reminder that cyber threats can target anyone, and proactive, comprehensive measures are essential.

Stay tuned for more insights and strategies to fortify your cybersecurity defenses in an ever-evolving digital landscape.