Sass-loader, a crucial webpack tool for compiling Sass/SCSS files, saw a minor version bump from 1.0.3 to 1.0.4 focusing on enhancements and dependency updates. Both versions share core dependencies like loader-utils, ensuring continued compatibility with webpack's loader ecosystem. Developers relying on Sass-loader for their styling workflows within webpack projects will find both versions functionally similar, with the newer release incorporating subtle refinements.
The key differences reside primarily in the devDependencies. Version 1.0.4 shows upgrades to several testing and build related dependencies, most notably should (assertion library), css-loader, style-loader and extract-text-webpack-plugin. While should was bumped from 5.0.1 to 7.0.2 and css-loader was upgraded from 0.9.1 to 0.15.6 and style-loader from 0.8.3 to 0.12.3. extract-text-webpack-plugin saw the biggest increase from 0.3.8 to 0.8.2. These upgrades suggest improvements in the testing environment, better CSS processing and extraction capabilities during the build process for version 1.0.4. The upgraded extract-text-webpack-plugin specifically allows for better handling of CSS extraction into separate files, potentially improving initial page load times in production environments. Developers already using version 1.0.3 can upgrade to 1.0.4 for a more refined development experience and potentially better optimized CSS output. Version 1.0.4 was released July 3rd 2015 whereas 1.0.3 was released July 22nd 2015. Both versions list node-sass as a peer dependency, meaning developers must explicitly install it.
All the vulnerabilities related to the version 1.0.4 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...');
}