Webpack version 4.34.0 introduces subtle refinements over its predecessor, version 4.33.0, primarily focusing on internal improvements and dependency updates that enhance stability and performance. While the core functionality remains consistent, developers might observe minor enhancements in build times and resource handling due to these under-the-hood optimizations.
A key consideration is that both versions share an identical set of core dependencies, ensuring a seamless transition for existing projects. Dependency versions for crucial packages like ajv, acorn, tapable, and webpack-sources are mirrored, minimizing the risk of breaking changes during upgrades. Similarly, the development dependencies, vital for testing and linting, are also aligned across both versions.
The most significant distinction lies in the deployment details. Webpack 4.34.0 features a slightly larger unpacked size (1,393,872 bytes) compared to 4.33.0 (1,390,320 bytes) potentially indicating minor code additions or modifications even if there are similar file count but it does not affect drastically the speed. Also, 4.34.0 feature more up-to-date files since was deployed on June 12, 2019, offering the advantage of bug fixes and potentially addressing any security vulnerabilities identified in the previous version. For developers, upgrading to 4.34.0 is recommended to leverage these incremental improvements, ensuring a smoother development experience and taking advantage of a more recent and potentially more stable build.
All the vulnerabilities related to the version 4.34.0 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.
