MFA Fatigue Attack: How Push-Notification Hacks Work and How to Stop Them
Written by Mario Canario, Sales and Marketing Manager, RedBird Technology Solutions
Last updated: January 7, 2025
Cyberattacks keep getting smarter. One threat growing fast across Wisconsin is the MFA Fatigue Attack. It tricks users with nonstop login prompts until someone taps Yes by mistake. When that happens, the attacker gets inside. This article breaks down what an MFA Fatigue Attack is, why it works, and how to shut it down before damage spreads.
Why MFA Fatigue Matters for Any Business
Many small and mid-size businesses feel safe because they already use multi-factor authentication. MFA is essential. It adds a layer of protection that passwords alone cannot provide.
However, hackers know this. So they have learned how to turn MFA into a pressure point.
They do not break the system.
They break your patience.
Because they send push notifications again and again, users may approve them just to stop the noise. That single approval can unlock email, files, shared drives, accounting systems, and cloud apps. For many businesses, this leads to ransomware, stolen data, and downtime.
When you understand how the attack works, you can stop it fast.
What an MFA Fatigue Attack Is
An MFA Fatigue Attack sends repeated authentication prompts to a user’s phone or device. The attacker already has the username and password. Now they just need the second factor.
So they spam notifications until someone gives in.
Why this attack works
Because many teams:
• Trust MFA too much
• Assume prompts are glitches
• Approve alerts without checking the source
• Get tired late at night
• Want the pop-ups to stop
This makes the attack simple but powerful.
How an MFA Fatigue Attack Starts
Although the attack seems sudden, it usually follows a clear chain.
Step 1: Credentials Are Stolen First
The attacker usually gets the password before they start. This may happen through:
• Phishing emails
• Fake login pages
• Dark-web credential leaks
• Weak or reused passwords
• Compromised contractors or vendors
Once they have the password, the attack begins.
Step 2: The Attacker Triggers Push Notifications
They log in with the stolen password.
Your MFA tool sends prompts to your phone.
The attacker repeats the login attempt over and over.
This can take minutes.
It can also last hours.
Step 3: The User Becomes “Fatigued”
This is the point of failure.
Because the phone will not stop buzzing, a user may think:
• “Maybe the system is broken.”
• “Maybe I tapped something earlier.”
• “Maybe IT is running a test.”
• “I just want this to stop.”
One tap gives the attacker full access.
Some attackers also message the victim pretending to be IT support. This is what happened during the Uber breach. They push. Then, they insist. Finally, the victim is guided into approving the request.
MFA Fatigue Attack: What Hackers Do Next
Once inside, attackers often move quickly.
They may:
• Steal files
• Move laterally through the network
• Change security settings
• Plant ransomware
• Take over cloud apps
• Access email for deeper phishing
• Create new admin accounts
A single approved MFA prompt can lead to weeks of recovery.
How to Defend Against an MFA Fatigue Attack
You can reduce the risk with clear steps that work for businesses of any size.
1. Tighten Your MFA Settings
Most businesses never review their MFA controls. But these settings can stop fatigue attacks.
Use these adjustments:
• Reduce how long a push notification stays valid
• Limit how many login attempts are allowed
• Block repeated attempts from unusual locations
• Require location-based confirmations
• Require biometrics when possible
• Flag excessive push traffic for review
Even small changes can break the attack chain.
2. Train Your Team to Spot the Signs
Because attackers rely on user confusion, training is one of the strongest defenses.
Teach employees to:
• Never approve a prompt they did not request
• Pause and ask IT if something feels off
• Report repeated notifications right away
• Watch for fake “tech support” messages
• Protect passwords more carefully
A fast internal report can stop an attack before it spreads.
3. Move Beyond Password-Heavy Security
Passwords remain the weakest link.
Attackers know that most MFA Fatigue Attacks start with a stolen password.
To reduce risk:
• Adopt FIDO2 security keys
• Require biometrics on supported devices
• Explore passwordless login for cloud apps
• Use Single Sign-On with strict policies
The less you rely on passwords, the harder it is for attackers to begin the chain.
4. Enforce Least Privilege Access
If a compromised account cannot access admin tools, servers, or sensitive files, an attacker cannot escalate.
Least privilege means:
• Every user gets only the access they need
• Admin roles are limited
• Contractors have time-limited access
• Privileged actions require re-authentication
This stops small breaches from becoming major ones.
5. Harden Your Systems
System hardening removes weak points before attackers find them.
This includes:
• Removing old accounts
• Updating firmware
• Patching outdated software
• Reviewing firewall rules
• Closing unused ports
• Disabling legacy authentication
When your system has fewer cracks, attackers have fewer paths inside.
6. Build Strong Vulnerability Management
Because threats change fast, ongoing vulnerability scanning is vital.
A strong program includes:
- Asset discovery
- Risk assessment
- Priority ranking
- Patch deployment
- Reporting
- Continuous review
Attackers move quickly. Your protection must move faster.
MFA Factors: How They Work and Where Attacks Target
Understanding the layers of MFA helps explain how fatigue attacks exploit the system.
Knowledge Factors
Something you know:
• Password
• PIN
• Security question
This is where most attacks begin.
Possession Factors
Something you have:
• Phone
• Hardware token
• Tablet
• Security card
Push notifications live here.
Inherence Factors
Something you are:
• Fingerprint
• Facial recognition
• Voice ID
• Iris scan
These are hardest to fake and hardest to fatigue.
Attackers target whichever factor is easiest. For most people, that is push-based authentication.
When MFA Is Strong and When It Fails
Below is a simple comparison to help your team understand the difference.
| MFA Setup | Strength | Risk Level |
| Password + push prompt | Medium | High (fatigue attacks) |
| Password + biometric | High | Low |
| Passwordless FIDO2 key | Very High | Very Low |
| Push notifications with no limit | Medium | Very High |
| Push notifications + rate limits | High | Medium |
Common Mistakes That Make MFA Fatigue Attacks Worse
Businesses often weaken their own security without realizing it.
These mistakes are most common:
• Allowing unlimited push attempts
• Giving users admin access by default
• Not training staff on MFA approval rules
• Allowing old accounts to stay active
• Reusing passwords across services
• Letting outdated devices stay in the field
Fixing these issues strengthens your defenses right away.
Quick Checklist: How to Stop MFA Fatigue Fast
Use this list in your IT playbook:
✓ Turn on rate limits for MFA attempts
✓ Block repeated requests from unusual locations
✓ Use biometrics when possible
✓ Never approve unexpected MFA prompts
✓ Report suspicious prompts immediately
✓ Update passwords and enforce strong rules
✓ Use passwordless security keys for high-risk roles
✓ Review access rights monthly
This gives your business a clear, repeatable plan.
RedBird Technology Solutions Can Help
If your business is in Milwaukee or anywhere in Wisconsin, you do not need to face MFA threats alone. RedBird Technology Solutions has more than 25 years of experience helping organizations stay secure, stable, and prepared.
If you want help improving MFA, reducing risk, or building a stronger cybersecurity plan, we offer a free, friendly consultation. No pressure. Just guidance.