Ts-loader is a TypeScript loader for webpack, facilitating the integration of TypeScript code into webpack-based projects. Version 0.7.1 is a minor update following version 0.7.0, both maintained under the MIT license and authored by James Brantly. A primary aspect developers consider when deciding updates is if there are new features, breaking changes or bug fixes. ts-loader 0.7.1 was released on November 10, 2015, shortly after version 0.7.0 which was released the same day.
Examining the data, the package dependencies and devDependencies between ts-loader versions 0.7.0 and 0.7.1 remain identical. Both versions rely on the same core dependencies such as arrify, colors, semver, loader-utils, object-assign, and enhanced-resolve for core functionality. Similarly, the development dependencies including testing and build tools like mocha, mkdirp, rimraf, webpack, fs-extra, babel-core, typescript, babel-loader, and escape-string-regexp are consistent across the two versions.
The most notable distinction between the two versions is the release date, with version 0.7.1 being released approximately 13 hours after version 0.7.0. This suggests that version 0.7.1 likely includes minor bug fixes or very small improvements over its predecessor. For developers already using version 0.7.0, upgrading to 0.7.1 is likely a low-risk endeavor, potentially addressing issues identified shortly after the initial 0.7.0 release. Developers should consult the changelog, if available, for precise details on what was addressed in the 0.7.1 version.
All the vulnerabilities related to the version 0.7.1 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...');
}