Sass version 1.17.4 represents a minor iteration on the 1.17.3 release, both versions offering developers a pure JavaScript implementation of the popular Sass stylesheet language. Key features like the MIT license, the repository location at git+https://github.com/sass/dart-sass.git and the dependency on chokidar (version ^2.0.0) remain consistent between the two, ensuring stability in core areas. Both are authored by Natalie Weizenbaum, further indicating a smooth continuation of the project's vision.
The primary difference lies in the updated build artifacts and release timing. Version 1.17.4 was released on April 3, 2019, subsequent to the March 15, 2019 release of version 1.17.3. While the file count in the distributed tarball remains at 4 for both, the unpacked size increased slightly from 674,043 bytes in 1.17.3 to 674,324 bytes in 1.17.4. This hints at minor adjustments or bug fixes incorporated into the newer version.
For developers, version 1.17.4 likely incorporates internal improvements, bug fixes, or very minor feature additions, making it the preferred choice for those seeking the most up-to-date, stable release within the 1.17.x series. Given the minimal changes, upgrading from 1.17.3 should be straightforward.
All the vulnerabilities related to the version 1.17.4 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.
