Browser Isolation

Browser isolation is a cybersecurity technique that separates web browsing activity from the local device or network to prevent malware, phishing, and malicious scripts from affecting the user’s system. 

Instead of processing web content on a user’s device, browser isolation renders web pages in a secure environment—either remotely or in a sandbox—then streams a safe visual representation back to the user.

This method is commonly used in high-security environments to reduce the attack surface caused by internet-borne threats.

What Is Browser Isolation?

Browser isolation refers to the process of executing browser code in a separate environment—either on a remote server (remote browser isolation) or within a local container (local isolation)—to protect the endpoint from threats such as:

• Zero-day attacks
• Drive-by downloads
• Malicious JavaScript
• Ransomware via the browser

Even if a user visits a compromised website, the isolation layer ensures no harmful code reaches the actual device.

Types of Browser Isolation

1. Remote Browser Isolation (RBI)

Web content is executed on a remote virtual machine or container. The user receives only a pixel stream (image or video) of the web session.

• Completely isolates web threats
• Used in enterprise networks
• High resource usage on the server side

2. Local Browser Isolation

The browser runs within a sandbox or a separate process on the user’s machine.

• Lower latency than RBI
• Still provides strong endpoint security
• Typically used for limited or specific sites

3. Clientless Browser Isolation

This method doesn’t require installing software on the user’s device. Browsing occurs through a cloud-hosted portal that displays the remote-rendered session.

How Browser Isolation Works

Here’s a simplified workflow:

1. User clicks a web link
2. Instead of loading the site directly, the request is routed to an isolation environment
3. The page is rendered outside the local browser
4. A safe version of the content is displayed to the user (either via streaming, mirroring, or sanitization)

This process ensures that malicious scripts or file downloads never touch the endpoint system.

Benefits of Browser Isolation

✔ Malware Prevention

Isolated browsing environments block exploits, ransomware, and drive-by downloads—even if the website is compromised.

✔ Protection Against Phishing

Some solutions disable form submissions or sanitize scripts, making phishing pages ineffective.

✔ Compatibility with Modern Sites

Unlike blocking-based approaches, browser isolation lets users access full websites—including JavaScript-heavy apps—without risk.

✔ Reduced Dependency on Detection

Since nothing harmful reaches the endpoint, browser isolation avoids the cat-and-mouse game of antivirus and threat detection.

Limitations to Consider

• Performance: Remote isolation may introduce latency.
• Cost: Enterprise-grade RBI tools can be expensive.
• User Experience: Some visual features may degrade when streamed.

Browser Isolation vs. Browser Sandboxing

Use Cases for Browser Isolation

• Finance teams accessing unknown documents and links
• Customer service agents opening links from emails
• High-security industries like healthcare, law, and government

Remote workforce accessing cloud tools through unsecured networks