What is Whitelisting in Cybersecurity? All You Need to Know

Network security is an essential step to ensure smooth communication and day-to-day operations. However, organizations struggle to keep their organization secure. One major reason is the lack of implementation of whitelisting, which is a powerful strategy. The issue arises when most teams in the organization aren’t sure what whitelisting means or how to whitelist domains properly. 

Without clear guidance on what whitelisting is, there are chances of blocking legitimate access or, worse, allowing unauthorized traffic into systems. These issues can lead to security gaps, delivery issues and increase chances of phishing attacks. For resolving security issues and strengthening cybersecurity posture, it’s necessary to understand and implement whitelisting effectively.

In this blog, we will understand what is whitelisting, its various types, and when to use it.

What is Whitelisting?

Whitelisting is a cybersecurity strategy in which only pre-approved or trusted users are allowed to operate on a system or network. It helps to reduce the risk of malware infection and unauthorized access through cyber intrusion. In a whitelisting strategy for access control involves a procedure for creating a list of trusted entities, such as IP addresses, applications or email addresses, to allow access.

Various Types of Whitelisting Strategies

Following are the various types of whitelisting strategies mentioned below:

• IP Whitelisting: It allows only specific IP addresses to access a system or network and helps in enhancing security.
• Email Whitelisting: This strategy helps to filter emails to ensure they are received in the inbox through trusted senders only. It also reduces phishing attempts and spam mail.
• Domain Whitelisting: Helpful in the corporate environment to control internet usage by restricting access to approved websites or domains.
• Application Whitelisting: Through this whitelisting strategy, it ensures that only pre-approved software can be installed or executed on the device.
• Website Whitelisting: By using this approach, organizations can restrict access to specific websites to minimize exposure to modern cyberthreats.

Example  of a Secure Corporate VPN

Scenario

A company wants to implement a whitelisting process to ensure only authorized employees of the organization can access its internal systems via VPN.

Whitelisting Procedure

• When the user attempts to connect to the VPN, the server checks the device’s IP address.
• For successful implementation of whitelisting strategy, organizations need to maintain a list of employee’s devices and their IP address. These IP addresses will be added to the whitelist on the VPN server.

For IP addresses present on the Whitelist

• In this scenario, access to the VPN is granted which allows the user to access internal resources such as databases or file servers.

For an IP address absent from the Whitelist

• The connection gets denied even if the user has valid credentials.

Applications of Whitelisting

1. It helps in reducing false positives when compared to blacklisting by monitoring on approved entities.
2. Usually, brands use whitelisting techniques for targeted Ads to control who is seeing the Ads.
3. Helps in establishing strict control over system access by ensuring only necessary applications are used.
4. By blocking unauthorized software, it helps to reduce the risk of potential malware.
5. Reduces the risk of cyber threats by allowing trusted sources only.
6. Focusing on trusted entities helps to simplify security management procedures.
7. Many organizations mandate whitelisting to meet regulatory compliance which helps in strengthening cybersecurity posture.

Blacklisting vs Whitelisting: A Cybersecurity Perspective

Parameter	Blacklisting	Whitelisting
Access Control	It blocks the known bad entities.	It allows only known good entities
Default Behavior	Blacklisting default behavior is to allow all except the blocked ones.	The default behavior involves blocking all except the allowed ones.
Security Level	The security level is moderate, usually depending on the updated threat list.	It  has strict control over access to strengthen overall security
Management Efforts	It’s easier to update with new threats and requires low management effort.	Whitelisting requires constant vetting and updates
Threat Handling	Threat handling is reactive and focuses on identified threats	The threat-handling process is proactive and helps in preventing from unknown cyber threats
Common Use Case	It is commonly used in email filters and antivirus software.	The common use of whitelisting is involved in application allowlists and firewall rules.

When to use Whitelisting?

Whitelisting can be helpful in an environment where strict access control and security are the priority.

Following are the situations described below where whitelisting can be useful :

1. Critical infrastructures such as government, military, or financial firms cannot afford the risk of unauthorized access and malicious activities.
2. For healthcare and financial industries, whitelisting is a must as regulatory requirements are strict and require proper control over various data and systems.
3. For institutions such as schools, colleges, and offices, a controlled environment is a necessity which requires the usage of only approved apps and software. Establishing a strict security posture helps to prevent data breaches and the use of unauthorized apps.
4. For devices such as  IOT and embedded systems, whitelisting can be useful for industrial and automation purposes by restricting communication to trusted sources helping in preventing unauthorized access.
5. Helpful in protecting critical servers or endpoints to ensure only predefined users can access the systems.
6. Whitelisting can be used for enforcing access controls between segments of the network to ensure only approved traffic gets access.
7. To manage external vendors, whitelisting plays a major role in that only verified IP addresses, applications or user accounts of trusted partners can interact with internal systems.
8. To reduce the risk of unauthorized logins and reduce the chances of brute-force attacks, whitelisting must be deployed by cloud service providers to allow access through specific IPs only.

Conclusion

Whitelisting is an important network security approach that permits access to only pre-approved trusted applications, users, and IP addresses. It helps in blocking all entities that are not explicitly allowed, making it an overall security method for preventing authorized access and data breaches. The whitelisting may require careful management to meet modern cybersecurity requirements. Organizations must use various whitelisting strategies that can help meet modern compliance requirements, protect critical infrastructure, and minimize security risks.

Frequently Asked Questions (FAQs)