---
title: Client-Side Security
description: Cloudflare Client-Side Security defends against browser supply chain attacks. Simplify PCI DSS compliance, block Magecart-style attacks, and more.
image: https://www.cloudflare.com/preview.png
---

 Client-Side Security 

##  Client-Side Security 

###  Backed by Cloudflare's world-class threat intelligence and machine learning capabilities, Client-Side Security helps defend against browser supply chain attacks that target vulnerable JavaScript dependencies. Simplify PCI DSS compliance, block Magecart-style attacks, and boost visibility into web resources. 

[  Talk to an expert ](https://www.cloudflare.com/resource/contact-enterprise-sales/) [  Get started ](https://dash.cloudflare.com/sign-up) 

**Intelligent attack prevention** 

Machine learning-based protection and threat intelligence drawn from protecting \~20% of all Internet properties. 

**Improved visibility** 

Track your third-party scripts, cookies, and active connections from in a single pane of glass. 

**Automatic threat alerts** 

Instant notifications when new scripts are detected, marked as malicious, or loaded from unknown domains. 

![Background Pattern](/static/pattern.png) 

####  Use cases 

 Ways to apply Client-Side Security 

[  Learn more ](https://cfl.re/ps-brief) 

 Meet compliance requirements 

Reduce third-party vendor risk and address client-side requirements for standards and regulations like PCI DSS, the GDPR, and more. 

 Prevent financial and identity theft 

Block browser-based attacks aimed at your users’ personal and financial information. 

 Go beyond content security policies (CSP) 

Monitor JavaScript dependencies and block threats with threat intelligence and machine learning that goes above and beyond CSPs. 

### Frequently asked questions

###### What is Cloudflare Client-Side Security?

Cloudflare Client-Side Security is a client-side security solution that helps protect users' personal and financial data. It defends websites against attacks targeting vulnerable JavaScript dependencies, from Magecart-style attacks that exfiltrate user data to cryptojacking attacks. Client-Side Security helps web apps maintain compliance with frameworks like PCI DSS and the GDPR.

###### How does Client-Side Security help protect websites?

Client-Side Security continuously monitors a website's third-party scripts and other loaded dependencies for any signs of malicious activity or compromise, such as unauthorized additions, connections, or changes. By using machine learning and Cloudflare's industry-leading threat intelligence, it can instantly identify, report, and block threats before they can affect the website or its visitors.

###### What are the main benefits of using Client-Side Security?

Client-Side Security prevents browser supply chain attacks, provides automatic alerts for any suspicious script activity, stops financial data theft, and offers assistance in meeting compliance requirements like the GDPR and PCI DSS.

###### How does Client-Side Security help with compliance?

Client-Side Security helps organizations address client-side security requirements. Specifically, it assists with meeting GDPR and PCI DSS standards for detecting compromised third-party scripts and providing alerts.

###### Can Client-Side Security prevent the theft of customer data?

Client-Side Security is designed to block browser-based attacks that are aimed at stealing the personal and financial information of your users.

###### Is Client-Side Security better than using a Content Security Policy (CSP)?

Client-Side Security offers protection that goes beyond a standard CSP. While a CSP provides a static set of rules for what resources can be loaded, Page Shield actively monitors JavaScript dependencies and uses advanced threat intelligence and machine learning to detect and block threats.

[ Compute ](/products/#compute) 

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[ Storage ](/products/#storage) 

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[ Security ](/products/#security) 

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[ Network & Content Delivery ](/products/#network) 

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# Build without boundaries

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[  Start building for free ](https://dash.cloudflare.com/sign-up) [  View docs ](https://developers.cloudflare.com/) 

 No cold starts or region complexity  SASE and Zero Trust without the complexity  Deploy to 330+ cities instantly  Defend against the Internet's biggest DDoS attacks  Predictable pricing without surprises  Identity-aware Zero Trust access that retires your VPN  Battle-tested infrastructure powering millions  CDN, WAF, and DNS faster than the public Internet  No cold starts or region complexity  SASE and Zero Trust without the complexity  Deploy to 330+ cities instantly  Defend against the Internet's biggest DDoS attacks  Predictable pricing without surprises  Identity-aware Zero Trust access that retires your VPN  Battle-tested infrastructure powering millions  CDN, WAF, and DNS faster than the public Internet

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