Sass version 1.13.4 represents a minor update over its predecessor, version 1.13.3, in this popular pure JavaScript implementation of the Sass stylesheet language. Both versions maintain core functionalities, providing developers with a robust tool for compiling .scss and .sass files into CSS. They share the same fundamental dependencies like "chokidar" for file watching, MIT license, and the same author, ensuring consistency in the underlying architecture and maintenance. The package's repository remains consistent, hosted on GitHub under the sass/dart-sass project, offering developers a centralized location for reporting issues and contributing.
However, differences exist primarily in nuances such as package size and release timing. Version 1.13.4 showcases a slightly smaller unpacked size (647630 bytes) compared to 1.13.3 (692621 bytes), suggesting optimizations or minor code alterations that reduce its footprint. Furthermore, 1.13.4 was released approximately two and half hours later than 1.13.3 on the same day, September 11, 2018. While seemingly insignificant, this time difference usually indicates that 1.13.3 had some serious problem fixed by 1.13.4. Developers should always use the latest stable version if possible, to inherit the benefit of bug fixes and general improvements.
All the vulnerabilities related to the version 1.13.4 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.
