Sass-loader is a Webpack loader that allows developers to import Sass/SCSS files directly into their JavaScript modules, streamlining CSS management within Webpack-based projects. Comparing version 3.0.0 with the previous stable version 2.0.1 reveals some subtle but important updates. Both share core dependencies like async and loader-utils, essential for asynchronous operations and Webpack loader utilities respectively.
The key differences primarily lie in the development dependencies and peer dependencies, often indicating support for newer versions of related tools. Version 3.0.0 specifies "webpack": "1.12.2" as dev dependency while the version 2.0.1 specifies "webpack": "^1.11.0". This hints at potential updates, bug fixes, or new features supported by the newer Webpack version integrated into the testing and building process of sass-loader. Furthermore, While both versions require node-sass and webpack as peer dependencies, version 3.0.0 align their version requirements "^3.3.3" and "^1.12.2" respectively by including them in the dev dependencies too meanwhile version 2.0.1 specifies only node-sass "^3.2.0" as peer dependency. Also the newer version removes extract-text-webpack-plugin as a dev dependency, potentially indicating a change in how CSS extraction is handled during development or testing. Developers should ensure their projects meet these peer dependency requirements to avoid compatibility issues. In summary, while both versions offer Sass loading capabilities, version 3.0.0 appears to be optimized for a slightly newer Webpack ecosystem.
All the vulnerabilities related to the version 3.0.0 of the package
Prototype pollution in webpack loader-utils
Prototype pollution vulnerability in function parseQuery in parseQuery.js in webpack loader-utils prior to version 2.0.3 via the name variable in parseQuery.js.
Prototype Pollution in JSON5 via Parse Method
The parse method of the JSON5 library before and including version 2.2.1 does not restrict parsing of keys named __proto__, allowing specially crafted strings to pollute the prototype of the resulting object.
This vulnerability pollutes the prototype of the object returned by JSON5.parse and not the global Object prototype, which is the commonly understood definition of Prototype Pollution. However, polluting the prototype of a single object can have significant security impact for an application if the object is later used in trusted operations.
This vulnerability could allow an attacker to set arbitrary and unexpected keys on the object returned from JSON5.parse. The actual impact will depend on how applications utilize the returned object and how they filter unwanted keys, but could include denial of service, cross-site scripting, elevation of privilege, and in extreme cases, remote code execution.
This vulnerability is patched in json5 v2.2.2 and later. A patch has also been backported for json5 v1 in versions v1.0.2 and later.
Suppose a developer wants to allow users and admins to perform some risky operation, but they want to restrict what non-admins can do. To accomplish this, they accept a JSON blob from the user, parse it using JSON5.parse, confirm that the provided data does not set some sensitive keys, and then performs the risky operation using the validated data:
const JSON5 = require('json5');
const doSomethingDangerous = (props) => {
if (props.isAdmin) {
console.log('Doing dangerous thing as admin.');
} else {
console.log('Doing dangerous thing as user.');
}
};
const secCheckKeysSet = (obj, searchKeys) => {
let searchKeyFound = false;
Object.keys(obj).forEach((key) => {
if (searchKeys.indexOf(key) > -1) {
searchKeyFound = true;
}
});
return searchKeyFound;
};
const props = JSON5.parse('{"foo": "bar"}');
if (!secCheckKeysSet(props, ['isAdmin', 'isMod'])) {
doSomethingDangerous(props); // "Doing dangerous thing as user."
} else {
throw new Error('Forbidden...');
}
If the user attempts to set the isAdmin key, their request will be rejected:
const props = JSON5.parse('{"foo": "bar", "isAdmin": true}');
if (!secCheckKeysSet(props, ['isAdmin', 'isMod'])) {
doSomethingDangerous(props);
} else {
throw new Error('Forbidden...'); // Error: Forbidden...
}
However, users can instead set the __proto__ key to {"isAdmin": true}. JSON5 will parse this key and will set the isAdmin key on the prototype of the returned object, allowing the user to bypass the security check and run their request as an admin:
const props = JSON5.parse('{"foo": "bar", "__proto__": {"isAdmin": true}}');
if (!secCheckKeysSet(props, ['isAdmin', 'isMod'])) {
doSomethingDangerous(props); // "Doing dangerous thing as admin."
} else {
throw new Error('Forbidden...');
}