What is Content Security Policy?
Content Security Policy (CSP) is a security standard that helps prevent cross-site scripting (XSS), clickjacking, and other code injection attacks. It works by allowing you to specify which sources of content are trusted and should be allowed to execute on your website.
Why CSP Matters
In today's interconnected web, your application may load resources from multiple sources - scripts from CDNs, images from external services, styles from various providers. CSP gives you control over these resources and helps prevent malicious code from executing.
How CSP Works
CSP works by defining a policy that tells the browser which sources are allowed for different types of content. When the browser encounters content that doesn't match the policy, it blocks it and reports the violation.
Basic CSP Example
Content-Security-Policy: default-src 'self';Here's a simple CSP header that only allows content from your own domain:
Key Benefits
- Prevents XSS attacks by controlling script execution
- Reduces the impact of data injection vulnerabilities
- Provides detailed reporting of policy violations
- Helps meet security compliance requirements
- Improves overall application security posture