Awesome Typescript Loader (atl) is a popular webpack loader that enables developers to seamlessly integrate TypeScript code into their webpack-based JavaScript projects. Version 5.2.1 represents a minor update over the previous stable version, 5.2.0, focusing primarily on expanding compatibility with newer TypeScript versions.
A key difference between the two versions lies in the peerDependencies field. Version 5.2.0 declares support only for Typescript version ^2.7, while version 5.2.1 broadens this range to include ^2.7 || ^3. This seemingly small change is crucial for developers using newer TypeScript versions (3.x), as it ensures compatibility and proper functionality without requiring downgrades or workarounds. Users can now leverage the latest TypeScript features and improvements with the loader.
No actual code was changed besides the peer dependency; therefore, both versions share the same core functionalities, including efficient TypeScript compilation, caching mechanisms for faster builds, and comprehensive error reporting. The packages maintain the same dependencies for core functionalities like chalk, enhanced-resolve, loader-utils, lodash, micromatch, mkdirp, source-map-support, and webpack-log. Developers benefit from having a well-maintained loader with a comprehensive set of features and a broad range of supported TypeScript releases which prevents version conflicts and simplifies build processes.
All the vulnerabilities related to the version 5.2.1 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.
