Webpack version 4.30.0 offers incremental improvements over the previous stable release, 4.29.6, primarily focusing on refinements and bug fixes rather than introducing groundbreaking new features. Both versions serve the same core purpose: bundling JavaScript and other assets for web browsers. Developers will find the familiar configuration options and module loading capabilities intact. A key area to observe is dependency updates. Examining the dependency lists, although mostly similar, subtle version bumps might address underlying security concerns or performance bottlenecks in underlying packages like ajv, acorn, potentially contributing to a more robust and secure development experience. Although the core functionalities remain consistent, these updates often translate to improved build times and stability. Developers should always review the changelog for comprehensive details, paying attention to bug fixes impacting specific use cases or edge cases they might encounter, but users who already have their webpack configuration well-defined should encounter no problems after updating. Although there are no very noticeable changes for webpack 4.30.0 respect to 4.29.6, the small improvements here and there can be helpful for performance or solve specific bugs.
All the vulnerabilities related to the version 4.30.0 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.
