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Feroot vs c/side

Monday, September 2nd, 2024

Updated July 1st, 2025

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Carlo D'Agnolo

This article takes an honest look at the features of Feroot.

Since you’re on the c/side website, we acknowledge our bias. That said, we’ve built our case honestly and based our analysis on publicly available information, industry information, objective technology analysis and our own or our customers' experiences.

If you want to verify their claims yourself, please navigate to their product page.

Criteria c/side Feroot
Approaches used Proxy + agent based detections
but also offers crawler and offers
a free CSP reporting endpoint
JS-Based Detection
Real-time Protection
Full Payload Analysis
Dynamic Threat Detection
DOM-Level Threat Detection
100% Historical Tracking & Forensics
Bypass Protection
Certainty the Script Seen by User is Monitored
AI-driven Script Analysis
QSA validated PCI dash
SOC 2 Type II
PCI specific UI

What is Feroot?

Feroot was founded to create a client-side security solution protecting dependencies, similar to c/side back in 2017. They combine two approaches to deliver their security claims.

How Feroot works

Feroot’s offering is split into two products: “PageGuard” and “Inspector”.

Feroot PageGuard

Their PageGuard page reads:

“PageGuard deploys security permissions and policies to JavaScript-based web applications to continuously protect them from malicious client-side activities, malware, and third-party scripts.”

And:

“PageGuard overwrites certain main and core JavaScript code to protect your web application from client-side cyber threats.”

It’s clear they largely follow the same approach as most of our competitors. They use permissions and a form on an allow-list where you pre-approve which scripts are allowed to run on which pages.

There are a few problems with this approach.

If only the source of the script is checked using an allow-list, it has no clue which code get's served.

PageGuard would not have caught the biggest client-side attack of 2024, the Polyfill attack. Here a domain changed ownership and suddenly the script code changed. If only the source of the script is checked using an allow-list, it has no clue which code get's served. Solely relying on this is not safe.

Feroot Inspector

Their “Inspector”, deploys synthetic users disguised as honeypot customers, to simulate real user behavior. Inspector’s synthetic users are able to complete real user tasks and are able to identify malicious scripts and unauthorized actions on JavaScript web assets. This is a somewhat similar approach to Reflectiz.

This is effectively a crawler that does periodic checks on pages. A crawler can easily be avoided by only serving malicious scripts to residential IP adressess. Based on various parameters, like different user agents, different client-side scripts are served.

A crawler on its own can not meet PCI DSS requirements since one of the requirements is implementing 'a mechanism to prevent unauthorized scripts'.

How c/side goes further

c/side primarily offers a hybrid proxy approach which sits in between the user session and the 3rd party service. It analyzes the served dependencies code in real-time before serving it to the user.

This allows us to not only spot advanced highly targeted attacks and alert on them, c/side also makes it possible to block attacks before they touch the user's browser. It also checks the box for multiple compliance frameworks, including PCI DSS 4.0.1. We even provide deep forensics, including if an attacker bypasses our detections. Allowing you to more tightly scope the size of the incident us to make our detection capabilities better every day. No other vendor has this capability.

We believe this is the most secure way to monitor and protect your dependencies across your entire website. We've spent years in the client-side security space before we started c/side, we've seen it all, this is the only way you can actually spot an attack.

Sign up or book a demo to get started.

FAQ

Q: How does c/side's hybrid proxy differ from Feroot's JavaScript agent approach?

A: The fundamental difference is timing of protection. Feroot deploys JavaScript agents in browsers that monitor for malicious behavior after scripts have already loaded and begun executing. c/side's hybrid proxy intercepts and analyzes every script before it reaches browsers, blocking malicious content at the network level. We prevent attacks from happening, while Feroot detects them after they've already been delivered to users.

Q: Can attackers bypass c/side's protection like they can with Feroot's browser-based agents?

A: No, because c/side's core analysis happens on our proxy, completely invisible to attackers.  Feroot's JavaScript monitoring agents run in the browser where sophisticated attackers can detect, analyze, and potentially disable them. Attackers can craft code specifically designed to avoid triggering the behavioral monitoring. c/side's proxy protection occurs server-side before content reaches browsers, making our security mechanisms completely invisible and impossible for attackers to study or circumvent.

Q: What forensic evidence does c/side provide compared to Feroot's behavioral monitoring?

A: Feroot provides behavioral alerts and monitoring data when suspicious activity is detected, but c/side captures and preserves the exact malicious code that was blocked. This gives you complete forensic evidence showing precisely what the attack looked like and what data it was designed to steal. Auditors get immutable proof of the actual attack code rather than just behavioral observations that may not capture the full threat.

Q: How do regulatory compliance capabilities compare between c/side and Feroot?

A: c/side provides comprehensive PCI DSS compliance with immutable payload archives and detailed audit trails covering both requirements 6.4.3 and 11.6.1. Feroot's behavioral monitoring approach provides detection logs but lacks the forensic-grade evidence and historical tracking that regulators increasingly require. Our approach creates the complete documentation that compliance officers need for thorough regulatory reporting.

Q: Why is c/side's prevention approach better than Feroot's detection approach?

A: Prevention stops attacks before any damage occurs, while detection only alerts you after malicious scripts have already executed in users' browsers. With Feroot's approach, sensitive data can be stolen in milliseconds before the monitoring system detects the attack. c/side's proxy ensures malicious scripts never get the chance to interact with user data because they're blocked before reaching browsers entirely.

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More About Carlo D'Agnolo

I work on Marketing at c/side.