CSP Evaluator Core Library
Introduction
Please note: this is not an official Google product.
CSP Evaluator allows developers and security experts to check if a Content
Security Policy (CSP) serves as a
strong mitigation against
cross-site scripting attacks.
It assists with the process of reviewing CSP policies, and helps identify subtle
CSP bypasses which undermine the value of a policy. CSP Evaluator checks are
based on a large-scale study
and are aimed to help developers to harden their CSP and improve the security of
their applications. This tool is provided only for the convenience of developers
and Google provides no guarantees or warranties for this tool.
CSP Evaluator comes with a built-in list of common CSP allowlist bypasses which
reduce the security of a policy. This list only contains popular bypasses and is
by no means complete.
The CSP Evaluator library + frontend is deployed here:
https://csp-evaluator.withgoogle.com/
Installing
This library is published to https://www.npmjs.com/package/csp_evaluator
. You
can install it via:
npm install csp_evaluator
Building
To build, run:
npm install && tsc --build
Testing
To run unit tests, run:
npm install && npm test
Example Usage
import {CspEvaluator} from "csp_evaluator/dist/evaluator.js";
import {CspParser} from "csp_evaluator/dist/parser.js";
const parsed = new CspParser("script-src https://google.com").csp;
console.log(new CspEvaluator(parsed).evaluate());