Understanding Identity-Based Attacks: Credential Stuffing, MFA Fatigue, and More
- Jonathan Lanyon
- Mar 2
- 4 min read
Updated: Mar 15
Identity-based attacks have become a major threat to digital security. As organizations and individuals rely more on online accounts and digital identities, attackers focus on exploiting these identities to gain unauthorized access. This shift makes identity and access management (IAM) a critical defense line. This post explores key identity-based attack methods such as credential stuffing, MFA fatigue, session hijacking, and OAuth abuse, explaining how they work and what can be done to protect against them.
Credential Stuffing and Its Growing Threat
Credential stuffing is an automated attack where hackers use stolen username and password combinations from one breach to try logging into other services. Because many people reuse passwords across sites, attackers can gain access to multiple accounts with little effort.
How Credential Stuffing Works
Attackers obtain large databases of leaked credentials from data breaches.
They use automated tools to test these credentials on popular websites.
When a match is found, they gain access to the victim’s account.
These accounts can be used for fraud, identity theft, or further attacks.
Real-World Impact
In 2023, a major streaming service reported a surge in account takeovers linked to credential stuffing. Attackers used stolen credentials to access premium accounts, causing financial losses and customer frustration. This example shows how credential stuffing can affect both users and businesses.
Defense Strategies
Use unique, strong passwords for every account.
Employ password managers to generate and store complex passwords.
Implement rate limiting and IP blocking to slow down automated login attempts.
Monitor for unusual login patterns and failed login spikes.
MFA Fatigue Attacks and Why They Work
Multi-factor authentication (MFA) adds a second layer of security by requiring users to verify their identity through a device or app. However, attackers have found ways to exploit MFA through fatigue attacks.
What Is MFA Fatigue?
MFA fatigue happens when attackers send repeated authentication requests to a user’s device, hoping the user will approve one out of frustration or confusion. This social engineering tactic relies on overwhelming the user with notifications.
How Attackers Use MFA Fatigue
Attackers obtain valid credentials through phishing or other means.
They attempt to log in, triggering MFA push notifications.
They send hundreds of requests in a short time to annoy the user.
The user eventually approves a request, unknowingly granting access.
Examples and Consequences
A recent incident involved a government employee who received dozens of MFA prompts within minutes. Exhausted, the employee approved one, allowing attackers to access sensitive systems. This shows how MFA fatigue can bypass strong security controls.
Preventing MFA Fatigue
Educate users about MFA fatigue and how to respond.
Use MFA methods less prone to fatigue, such as hardware tokens or biometrics.
Implement adaptive authentication that detects unusual login behavior.
Limit the number of MFA prompts sent within a time frame.
Session Hijacking and Its Risks
Session hijacking involves stealing or manipulating a user’s active session to gain unauthorized access without needing credentials again. Attackers exploit vulnerabilities in session management or intercept session tokens.
How Session Hijacking Happens
Attackers intercept session cookies through unsecured Wi-Fi or malware.
They use stolen tokens to impersonate the user.
They can perform actions as the user, such as transferring funds or changing settings.
Notable Cases
In 2022, a popular online banking platform suffered session hijacking attacks where attackers used stolen session tokens to drain accounts. The bank had to freeze transactions and improve session security after the breach.
Mitigation Techniques
Use secure, encrypted connections (HTTPS) to protect session data.
Implement short session timeouts and automatic logouts.
Use token binding to tie sessions to specific devices.
Monitor for unusual session activity and multiple logins from different locations.
OAuth Abuse and Its Emerging Threat
OAuth is a widely used authorization framework that allows users to grant third-party apps access to their data without sharing passwords. While convenient, OAuth can be abused by attackers to gain unauthorized access.
How OAuth Abuse Occurs
Attackers create malicious apps that request excessive permissions.
Users unknowingly grant access to these apps.
Attackers use the granted tokens to access user data or services.
Examples of OAuth Abuse
In 2023, a phishing campaign tricked users into authorizing a fake app that harvested email contacts and sent spam. This abuse of OAuth permissions caused reputational damage and user distrust.
Protecting Against OAuth Abuse
Educate users to review app permissions carefully.
Use OAuth consent screens that clearly explain requested access.
Regularly audit and revoke unused or suspicious app permissions.
Implement strict app registration and verification processes.
Why IAM Is the New Front Line
Identity and Access Management (IAM) systems control who can access what within an organization. With identity-based attacks on the rise, IAM becomes the frontline defense.
Key IAM Practices to Strengthen Security
Enforce strong authentication methods beyond passwords.
Use role-based access control to limit permissions.
Continuously monitor and analyze access patterns.
Automate identity lifecycle management to remove stale accounts.
The Role of User Awareness
Technology alone cannot stop identity attacks. Training users to recognize phishing, MFA fatigue, and suspicious app requests is essential.
Future Trends
Increased use of biometric authentication.
AI-driven detection of identity anomalies.
More granular access controls based on context and behavior.
Identity-based attacks will continue evolving, but strong IAM combined with user vigilance can reduce risks significantly.
Comments