Website blocklisting is the process of identifying and blocking access to websites that are considered harmful, unsafe, or inappropriate. These sites may host malware, phishing scams, illegal content, or cause distractions and productivity loss. The main benefit of blocklisting is improved security, as it helps protect users and systems from cyber threats, data breaches, and malicious downloads. Blocklisting is commonly used by organizations, schools, and individuals to maintain control, enhance productivity, reduce exposure to online risks, and to promote a safe online work environment.
Steps to blocklist websites in your organization:
Follow the below steps to blocklist websites, using Cloud Protection:
- Select Cloud Protection from the application drop-down.
- Go to Configuration > Control Policies > Advanced URL filtering.
Use the default policies or create custom ones using a single condition or a combination of filters for more precise control. Commonly used filters include
Domain -instagram.com, free-cracked-software.xyz, flipkart.com, *.torrentdownloads.pro
Request URI - /reels, /games, accounts/password/reset, /download
Browser - Internet Explorer, Opera, Safari
Domain reputation - <40, <30
Domain Category - Gambling, social media, games, illegal
Request Size - > 50MB
Request header - User-Agent: Mozilla/5.0, Windows NT 10.0; Win64; x64, Chrome/120.0
Protocol - HTTP
Using a combinations of these filters, users can address a wide range of web access control and security use cases, such as:
- Allow social media usage but block uploads
- Allow Git Push only for developers
- Block large personal cloud uploads to Gdrive, Dropbox, etc.
- Restrict large downloads from high-risk category sites
- Restrict suspicious API data transfers over non-standard protocols
To configure and manage URL filtering policies, follow the steps shared in this page.
Click on Cloud App Control to blocklist websites based on their categories or reputation scores.
Category-based cloud app control
Block access to the selected website categories such as keyloggers and monitoring, news and media, spyware and adware. You can select the categories and move it to the Blocked Categories.
Reputation score-based cloud app control
The reputation score-based cloud app will block websites such as free hosting sites, low traffic sites with unknown value or score below the defined value. Configure the Reputation Settings based on your needs.
Additionally, you can use URL lookup wherein you can enter the URL or domain to check its category and reputation score.
Frequently asked questions
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1. What is website blocklisting? How is it different from website allowlisting?
Website blocklisting is the practice of blocking access to specific websites identified as harmful, unsafe, or unwanted. These websites may host malware, phishing content, illegal material, or cause productivity loss. Blocklisting prevents users from accessing such sites through devices, browsers, networks, or security systems. While allowlisting allows access only to approved websites and blocks all others by default. Allowlisting is more restrictive and secure, while blocklisting is easier to manage but provides fewer restrictions.
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2. Why is website blocklisting essential for enforcing security policy?
Administrators and CISOs use website blocklisting to reduce cybersecurity risks, prevent data breaches, and enforce organizational policies. Blocking malicious or risky websites helps protect networks from malware, phishing attacks, and compliance violations, while ensuring safer internet usage for employees, systems, and other business-critical infrastructure.
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3. How does website blocklisting work in general? Does blocklisting affect all users working in a company?
Website blocklisting works by intercepting web requests and blocking access to listed domains or URLs. This is commonly implemented through DNS filtering, proxy servers, endpoint security tools, or browser controls, which deny connections and display warning or access-denied messages. It depends on where blocklisting is applied. Network-level or firewall-based blocklisting affects all users, while device-level or user-based policies may apply only to specific teams or roles. Administrators can control scope based on organizational needs and security policies.
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4. What are the indicators of a shady app or website that should be blocklisted?
Indicators include frequent pop-ups, forced downloads, fake login pages, mismatched URLs, poor SSL certificates, excessive permissions, suspicious redirects, malware alerts, or reports from threat intelligence sources. Such signs suggest the website poses security or privacy risks and should be blocked.
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5. How often should a blocklist be reviewed or updated?
Blocklists should regularly be reviewed monthly or quarterly and immediately after security incidents. Continuous updates ensure newly identified threats are blocked and unnecessary or outdated entries are removed, maintaining an effective balance between security, accessibility, and operational efficiency.
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6. Can I blocklist a website on my personal computer? Is blocklisting a website permanent?
Yes, you can blocklist websites on a personal computer using browser settings, parental controls, the system hosts file, firewall rules, or third-party security software. These methods allow you to block specific websites locally without requiring network-wide or organizational-level controls. No, website blocklisting is not permanent. Blocklisted websites can be removed or modified at any time. Administrators or users can update the blocklist based on changing requirements, security assessments, or if a previously blocked website is later deemed safe or necessary.