Despite ongoing investments in security awareness training and strict data policies, breaches continue to happen. Employees are educated, business partners attest to following best practices, and security protocols are in place—yet cybercriminals still manage to break in. 

The hard truth? Many data breaches don’t happen because of a lack of policies but because attackers gain legitimate credentials. This type of incursion—called a Credentialed Access Breach—is both devastating and difficult to detect. 

So, what can be done? In this post, we’ll break down why credentialed access breaches persist and explore an effective strategy to limit their impact when they inevitably happen. 

What is a Credentialed Access Breach?

A credentialed access breach occurs when an attacker gains valid login credentials and impersonates a legitimate user. Unlike traditional hacking techniques that rely on brute force attacks or software exploits, these breaches bypass security defenses entirely because they appear as normal user activity. As a result, they can persist for months before being detected, often causing significant data exposure and financial loss. 

So, how exactly do attackers gain access to credentials? 

Phishing remains one of the most common and effective tactics. Cybercriminals pose as trusted sources such as a manager, IT support, or vendor to trick employees into revealing their credentials. According to Verizon’s 2023 Data Breach Investigations Report, 36% of all breaches involved phishing. Attackers leverage AI to craft highly personalized and realistic phishing emails, making them harder to detect. 

Credential leaks provide attackers with access to billions of compromised usernames and passwords from past data breaches. These credentials are frequently sold on underground forums and dark web marketplaces, fueling automated credential stuffing attacks. In 2021, a LinkedIn breach exposed 700 million user records, which were later exploited in such attacks. Even employees who use unique passwords for each account can still be at risk if multi-factor authentication is not enforced. 

Insider threats, both intentional and accidental, also contribute to credentialed access breaches. Malicious insiders such as disgruntled employees or contractors may leak credentials for financial gain or revenge. Unintentional insider errors are equally dangerous, such as employees accidentally emailing sensitive information to the wrong person or using weak passwords that are easily compromised. In a widely publicized case, an NHS employee mistakenly sent 700 patient records to an unauthorized recipient, leading to a major privacy breach. 

Why Credentialed Access Breaches Are Increasing 

Most companies take data security seriously. They invest in security awareness training, phishing simulations, and strong authentication protocols. Yet credential-based breaches continue to rise, often outpacing even the most advanced security defenses. 

Several key factors contribute to this growing threat: 

Stolen Credentials Are Everywhere 

The sheer volume of stolen credentials in circulation is staggering. The RockYou2021 breach alone exposed 8.4 billion passwords, flooding underground markets with login data. Attackers use these credentials in automated credential stuffing attacks, testing them across multiple platforms to gain access. Even employees with good security habits may still be vulnerable if their past credentials are exposed and reused. 

Phishing and Social Engineering Have Evolved 

Cybercriminals are now leveraging AI-generated phishing emails, deepfake technology, and advanced social engineering techniques to make phishing scams more convincing than ever. These tactics allow attackers to create hyper-personalized messages that can easily trick even the most security-conscious employees. Standard email filtering and training programs struggle to keep up as phishing tactics evolve rapidly. 

The Expansion of Remote Work and Cloud Services Has Increased Attack Surfaces 

The shift to cloud services, remote work, and SaaS platforms has dramatically expanded the number of access points for attackers. Employees now log into more systems than ever before, each one representing a potential entry point for cybercriminals. Every additional application, collaboration tool, and cloud storage service increases the risk of credential theft. 

Credentialed Access Breaches Take an Average of 328 Days to Detect 

Unlike malware-based attacks that trigger firewall alerts or antivirus warnings, credentialed access breaches often go unnoticed because attackers appear to be legitimate users. An attacker using stolen credentials may access systems for months without raising suspicion, extracting sensitive data over time. On average, it takes 328 days for organizations to detect these breaches, giving attackers nearly a year of undetected access to confidential information. Many organizations lack the advanced monitoring tools needed to detect anomalies, allowing breaches to persist unnoticed. 

As credential-based attacks grow more sophisticated, automated, and difficult to detect, companies must move beyond just preventing breaches. The new focus must be on minimizing the damage when breaches occur. 

One of the most effective strategies for limiting the impact of credentialed access breaches is data consumption rate limiting. 

What is Data Consumption Rate Limiting? 

How Rate Limiting Works 

Data consumption rate limiting controls how much sensitive information a user, based on their role, can access within a set timeframe. This ensures that even if an attacker gains valid credentials, they cannot extract large amounts of data at once. It functions similarly to how credit card companies detect fraud—by flagging and limiting unusual activity.  

For example, if an attacker compromises a nurse’s login credentials and attempts to access a hospital’s prescription database, rate limiting would prevent them from retrieving more than 10 records per hour. This threshold is based on normal user behavior, ensuring that legitimate access remains uninterrupted while blocking large-scale data theft. 

Why Rate Limiting by Role is Effective 

Rate limiting by role is a powerful security control that ensures data access is restricted based on an individual’s job function and normal usage patterns. By applying customized data consumption limits per role, organizations can prevent large-scale data leaks, maintain business continuity, and reduce compliance risks—all without disrupting legitimate access.  

1.Prevents Mass Data Exfiltration, Even with Stolen Credentials 

A common challenge in security is that once an attacker gains valid credentials, they often have unrestricted access to vast amounts of sensitive data. Rate limiting by role automatically restricts how much data can be retrieved at a time, preventing large-scale exfiltration, even if an attacker is using a legitimate account.

2. Aligns with Least Privilege Principles

The principle of least privilege dictates that users should only have access to the data necessary for their job. Rate limiting extends this approach by ensuring that even when access is granted, it remains restricted to reasonable levels based on typical usage patterns.  

3. Detects and Disrupts Anomalous Behavior

Cybercriminals using stolen credentials typically operate differently than legitimate users. They may attempt to download massive amounts of data in a short time or query sensitive records far outside normal work hours. Rate limiting acts as a tripwire, flagging and restricting suspicious access patterns before major damage is done.  

4. Reduces Compliance and Regulatory Risks 

Many data protection laws, including GDPR, CCPA, and HIPAA, require organizations to limit unnecessary access to sensitive data. By implementing role-based rate limiting, organizations can demonstrate proactive compliance with these regulations. 

Additionally, by restricting how much data an attacker can extract at once, companies reduce the total number of exposed records in a breach. This can help avoid mandatory breach notifications and reduce regulatory fines. 

5. Protects Against Insider Threats Without Blocking Legitimate Users 

Not all data breaches come from external hackers. Disgruntled employees, contractors, and business partners with valid access can intentionally leak or sell sensitive data. Traditional access controls struggle to differentiate between normal and malicious activity, making it easy for insiders to exfiltrate large amounts of data over time. 

Role-based rate limiting restricts how much data any one user can extract, making it significantly harder for insiders to cause damage. However, it does not interfere with daily workflows—legitimate users can still perform their tasks without experiencing unnecessary restrictions. 

6. Complements Existing Security Measures Without Adding Complexity 

Many security measures—such as multi-factor authentication, encryption, and anomaly detection—focus on keeping attackers out. However, once an attacker gets in, these controls do little to stop data exfiltration. Rate limiting by role fills this gap by controlling how much data can be accessed, even if authentication and perimeter defenses fail. 

Additionally, rate limiting is easy to implement and does not require major infrastructure changes. Unlike traditional security measures that can slow down operations or frustrate users, rate limiting works silently in the background, allowing normal business processes to continue while blocking excessive or suspicious access attempts. 

How ALTR’s Rate Limiting Protects Your Data 

ALTR’s data consumption rate limiting provides an intelligent, automated safeguard that restricts data access at the role level, ensuring that even if credentials are compromised, attackers cannot execute mass data exfiltration. With seamless integration into Snowflake and other cloud environments, ALTR helps organizations enforce least privilege, mitigate insider threats, and reduce compliance exposure—all without disrupting legitimate business operations. By implementing rate limits that align with real user behavior, ALTR ensures that your data remains protected, even when authentication controls fail.  

Learn how ALTR can help you lock down your sensitive data before a breach happens.