Why Multi-Factor Authentication (MFA) Stops Email Account Takeover

It’s around 4:30 PM here, my third cup of filter coffee cooling beside me, and I just finished a call with one of the banks we recently assisted moving to a more stringent zero-trust framework. Somewhat still dizzy thinking about what happened last week — another client nearly lost access to their CEO’s inbox because someone reused a password. Again. So felt like the right time to sit down and write this. Because if you are still counting on just passwords to protect access to your email… you’re wide open to trouble. And to be frank, we’ve seen this movie. Let’s see why Multi-Factor Authentication—MFA—is one of the bare minimums we have in email security today.

What Is Multi-Factor Authentication?

MFA = Multi-Factor Authentication, which is exactly what it is — from MFA. It’s a security process whereby users are required to prove their identity in more than one way before being granted access. So rather than entering just a username and password (something you know), you could:

• Provide a one-time password that is received by SMS (what you have).
• Biometrics (something you are), such as a fingerprint or face scan.
• One touch approve on an authenticator app (everyone digs pushing a button, no?)

The premise is simple: even if a hacker gains access to your password somehow —through phishing, brute forcing, or credential stuffing, say —they cannot get in unless they also have the second (or third) factor. Or, trying to hotwire a car when the keys, GPS, and sucker fuel are in separate places.

Quick Take

If you don’t have time, here’s the deal:

• Passwords only = just not cutting anymore.
• 99% of common credential-based attacks are prevented by MFA.
• Email accounts and especially BEC attempts make it highly important.
• MFA is easier than it has ever been to implement.
• PJ Networks does this daily for our customers to provide them a clean and locked mailbox.

You wouldn’t leave your server room door unlocked, right? So why are you leaving your digital front door unlocked?

Question 1: Why Passwords Alone Aren’t Enough

Let me turn back the clock a little bit. In 2003, I was managing the aftermath of the Slammer worm. We were in triage mode — patching, isolating, restoring systems. It was chaos. But in those days, strong passwords and perimeter firewalls were about all we had. Today? Not even close. Well, here’s the thing: everyone knows passwords suck. And yet we continue to give passwords far too much credit.

Think about it:

• Users are prone to reusing passwords across accounts. A breach at one app is a breach in your Outlook.
• Even good passwords can be phished given a convincing enough fake login page.
• Password complexity rules simply make users append a “1!” to the end of their pet’s name.

“Change it every 30 days.” Remember those IT policies? That did nothing but make employees cycle through Password1, Password2, etc. I can’t directly count the number of times I’ve seen a CFO reuse a Gmail login for their Office 365 admin account. (Yes, really.)

Real Talk from the Field

Last month, we assisted a manufacturing client in Pune to recover from a very subtle business email compromise. Hacker, had correct credentials (data stolen in a breach 2y ago), logged in at 2:43 AM, created forwarding rules that auto-deleted responses to certain mails, and fired up a fake payment instruction. The only reason we think something went wrong? It was that the hacker altered the email signature and someone caught on. If MFA had been in place? That second bit of login factor would’ve blown ’em up. Game over.

MFA Implementation Best Practices

So you’re sold (or at least a bit interested). Great. But MFA isn’t just a flick of the switch and thumbs-up. It needs to be implemented properly. Here’s how we do it at PJ Networks, with lessons learned the hard way:

• Focus first on the high-value assets: email admin accounts, finance groups, HR — anyone a hacker loves
• App-auth not SMS-based. SMS OTPs can be intercepted. Google Authenticator or Microsoft Authenticator, or perhaps even hardware keys like Yubikey? Better.
• Remember to include alternative means. What If someone lose their phone? Be prepared with a safe, recorded fallback.
• Condition access policies: Request MFA to log in from a new device/location.
• Audit periodically. People turn things off. They forget. Or policies get foiled over time.

Also, keep it stupidly simple for your team to understand. Use analogies, use visuals. “When I do train teams, I tell them MFA is like locking your front door and then like a bolt lock, and then a thumbprint scanner on it.” You want it to be annoying to attackers but not to users.

Email Security & MFA Solutions by PJ Networks

This is where I expect I sound a little smug — and I am. Email security has been something we’ve taken very seriously since email became the attack vector of choice (between 2008 and 2012, imho). At PJ Networks we include MFA as one of the routine steps in the hardening of email security for all businesses. It doesn’t matter if it is Microsoft 365, Google Workspace, or a custom mail server, we bake in layered access control.

Our typical workflow:

• Audit existing infrastructure (and any dumb “password123” surprises lurking).
• Suggest whereabouts it makes the most sense to implement MFA. Deploy via Intune, Azure AD(SSO) or third-party SSO providers.
• Log login behavior and use SIEM tools to identify abnormal login patterns

We recently deployed 120+ mail accounts in a cooperative bank in Gujarat migrating users to enforced MFA with conditional policies enabled. In a week, we were able to detect three blocked login attempts from foreign IPs that would have gone unnoticed. That’s precisely the reason it does matter. You won’t necessarily see the attack until you have the tools looking for it.

Also, don’t fall for vendors who prey on you with “AI-powered” email protection that lacks actual controls. It’s the new magic word, but it’s not magic. Just because someone threw an algorithm into a captcha doesn’t make it MFA.

Conclusion

If you’re retired or retired, you used to be secure back in my network admin days when we thought that putting a heavy perimeter firewall and setting password expiry was “security.” The kind of thinking you just read today’s threat landscape scoffs at.

Email remains the #1 threat vector to your organisation’s crown jewels. HR records, financial approval, customer PII… When your inbox is commandeered, the person who takes it over doesn’t just peruse your mail — they become you. That is what makes Business Email Compromise so destructive — and financially rewarding for attackers.

MFA in account takeover prevention is not just good practice. It’s table stakes.

So if you’re reading this and you haven’t turned on MFA across your email systems, what are you waiting for? You had better find it fast, though.

From working with banks on their zero-trust modernization effort to parsing router config files in the aftermath of DefCon (for real—some of that hardware hacking stuff was next-level), I keep coming back to one takeaway:

Some people have a flashy impression of cyber attacks. Teenager in a hoodie, the dramatic command line, seizure-inducing green text. In practice, it’s more often the case that… a password is reused and no second factor used.

Let’s stop offering hackers that opportunity.

Enable MFA. Today. If you are unsure how to begin or would like assistance firming things up without interrupting day-to-day workflows—shoot me a note. Better yet, let’s talk over another cup of coffee.

MFA, Email Hacks prevention, Cybersecurity, Email Account takeover prevention

Because securing email accounts is not only best practice. It’s survival.