Sass-loader is a Webpack loader that allows you to import Sass/SCSS files directly into your JavaScript modules. Comparing versions 4.1.1 and 4.1.0, the core functionality remains consistent, with both versions sharing identical dependencies like async, loader-utils, and object-assign for asynchronous operations, utility functions within loaders, and object property merging, respectively. Development dependencies, crucial for testing and building, also remain unchanged, including tools like mocha for testing, jshint for code linting, webpack for bundling, and various loaders for handling different file types (css-loader, raw-loader, file-loader, style-loader).
The main difference lies within the peerDependencies. Version 4.1.1 declares compatibility with webpack versions ^2 || ^2.2.0-rc.0 || ^2.1.0-beta || ^1.12.6 while 4.1.0 supports only ^1.12.6 || ^2.1.0-beta. The node-sass support is the same for both versions ^3.4.2 || ^4.0.0. While seemingly minor, these changes are significant for developers. Using the latest version of sass-loader improves compatibility with newer webpack versions, specifically the v2 release candidates (2.2.0-rc.0). This resolves potential version conflicts and allows users to take advantage of the features and improvements offered by more recent webpack releases. Also, the later version was released approximately a week later, thus it probably includes bug fixes or small improvements. Therefore, always consider upgrading to the latest compatible version (4.1.1) for enhanced compatibility and a more stable experience.
All the vulnerabilities related to the version 4.1.1 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...');
}