Ts-loader version 5.2.2 builds upon its predecessor, version 5.2.1, with key updates primarily targeting the development dependencies used for building and testing the library itself. Both versions serve the same core purpose: acting as a TypeScript loader for webpack, enabling developers to seamlessly integrate TypeScript code into their webpack-based projects. The core dependencies, critical for the functionality of ts-loader like chalk, semver, micromatch, loader-utils, and enhanced-resolve, remain consistent across both versions, indicating that the fundamental mechanism of handling TypeScript compilation within webpack hasn't changed.
The notable difference lies in the updated versions of certain devDependencies. Version 5.2.2 upgrades husky to version ^1.0.0, karma to ^3.0.0, typescript to ^3.1.1, and webpack-cli to ^3.1.1, and jasmine-core to ^3.0.0 while version 5.2.1 uses husky@^0.14.3, karma@^2.0.0, typescript@^3.0.1, and webpack-cli@^2.1.2, and jasmine-core@^2.5.2. These updates suggest improvements and bug fixes done on the specified versions. While these changes are primarily relevant to the ts-loader development team, they can indirectly benefit developers using the library. Ensuring ts-loader is built and tested with the latest tooling contributes to its stability and reliability. Developers should examine the changelogs of these upgraded packages, especially Typescript, to understand potential implications, if any, on their projects. Version 5.2.2 also saw a decrease in unpacked size in comparison to version 5.2.1.
All the vulnerabilities related to the version 5.2.2 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.
