Webpack 4.27.1 is a patch release following closely after version 4.27.0, both versions maintaining the core functionality of a powerful module bundler used to package JavaScript applications for the web. Primarily designed for bundling CommonJs and AMD modules, webpack efficiently allows developers to split codebases into smaller, manageable bundles that can be loaded on demand, optimizing performance by reducing initial load times.
A key advantage of using webpack lies in its extensive loader support, enabling the preprocessing of various file types like JSON, JSX, ES7, CSS, and LESS. This support extends to custom loaders, giving developers unparalleled flexibility in how they handle different assets within their projects. Both versions include the same set of dependencies like ajv, acorn, tapable, and webpack-sources ensuring stability and continued functionality. The development dependencies, which include testing and linting tools like jest, eslint, and prettier, along with loaders for various file formats like pug, less, and typescript, remain consistent between the two versions.
The minimal version bump from 4.27.0 to 4.27.1 suggests that the changes are likely bug fixes and minor improvements rather than significant new features or API changes. Developers considering upgrading would benefit from reviewing the detailed changelog between these versions to understand the specific issues addressed and confirm compatibility with their existing webpack configurations. Given the negligible differences, users of 4.27.0 should find upgrading straightforward, potentially resolving minor issues and benefiting from increased stability.
All the vulnerabilities related to the version 4.27.1 of the package
Regular Expression Denial of Service (ReDoS) in micromatch
The NPM package micromatch prior to version 4.0.8 is vulnerable to Regular Expression Denial of Service (ReDoS). The vulnerability occurs in micromatch.braces() in index.js because the pattern .* will greedily match anything. By passing a malicious payload, the pattern matching will keep backtracking to the input while it doesn't find the closing bracket. As the input size increases, the consumption time will also increase until it causes the application to hang or slow down. There was a merged fix but further testing shows the issue persisted prior to https://github.com/micromatch/micromatch/pull/266. This issue should be mitigated by using a safe pattern that won't start backtracking the regular expression due to greedy matching.
Uncontrolled resource consumption in braces
The NPM package braces fails to limit the number of characters it can handle, which could lead to Memory Exhaustion. In lib/parse.js, if a malicious user sends "imbalanced braces" as input, the parsing will enter a loop, which will cause the program to start allocating heap memory without freeing it at any moment of the loop. Eventually, the JavaScript heap limit is reached, and the program will crash.
