Sass version 1.7.0 introduces subtle improvements over the preceding 1.6.2, while maintaining the core functionality developers rely on. Both versions offer a pure JavaScript implementation of the Sass stylesheet language, making them ideal for projects needing Sass compilation within a Node.js environment. A key feature, shared across both, is the dependency on chokidar for efficient file watching, beneficial for automatically recompiling Sass files on save during development.
The main difference lies in a slight version bump, potentially signaling bug fixes, performance enhancements, or minor feature additions within the core Sass engine. Developers should consult the official changelog for a detailed breakdown of these internal improvements. Specifically, version 1.7.0 shows an increase in unpackedSize compared to v1.6.2 (687516 vs 646307), suggesting more code, assets or enriched features packed within the package which could lead to a slightly larger footprint. Released just two days apart, version 1.7.0 quickly followed 1.6.2, indicating a possible hotfix or a very rapid update cycle addressing immediate issues surfaced. Both stay true to their MIT license, thus remaining free to incorporate into commercial and open-source projects. Developers interested in Sass for modern web development can be confident in the stability, but should evaluate whether new features or fixes present in 1.7.0 are worth upgrading from an earlier patch.
All the vulnerabilities related to the version 1.7.0 of the package
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.
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.
