Sass version 1.7.3 represents a minor update to the popular CSS preprocessor library, building upon version 1.7.2. Both versions, implemented in pure JavaScript, offer developers a way to enhance their CSS workflow through features like variables, nesting, mixins, and more. They both share the same core functionality, including the dependency on "chokidar" for file watching capabilities, crucial for automatically recompiling Sass files upon changes during development. The licensing remains consistent under the MIT license, ensuring broad usability across projects. Developed by Natalie Weizenbaum, the library’s source code is accessible via the official Dart Sass GitHub repository.
The key distinctions between the two versions lie primarily in under-the-hood improvements and potentially bug fixes. The "unpackedSize" in the "dist" section shows a difference. Version 1.7.3 is slightly larger, with an unpacked size of 686142 compared to 1.7.2's 647105 suggesting added features, refined code, or updated dependencies within the core Sass engine, even though the file count remains the same. Crucially, the release dates reveal a very short interval between releases, with version 1.7.3 being released just hours after 1.7.2. This quick succession suggests that version 1.7.3 is mainly focused on addressing some specific regression found on 1.7.2. Developers should consider upgrading to version 1.7.3 to benefit from these potential refinements and ensure they are using the most stable and up-to-date JavaScript Sass implementation.
All the vulnerabilities related to the version 1.7.3 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.
