Expect version 24.5.0 is a minor release of the assertion library primarily utilized within the Jest testing framework, building upon the foundation laid by version 24.4.0. Both versions serve the crucial function of providing the expect function, the cornerstone for writing expressive and reliable unit tests. Developers leverage expect to make assertions about their code's behavior, verifying that the output matches the intended results.
The key distinction lies primarily in upgraded dependencies. Notably, version 24.5.0 updates @jest/types, jest-message-util, and jest-matcher-utils to version 24.5.0. This indicates improvements and bug fixes within Jest's internal type definitions, message formatting, and matcher utilities. While outwardly the core API remains consistent, developers benefit from underlying improvements. The update of @jest/types suggests enhanced type safety, leading to more robust and maintainable tests. Similarly, the updated message and matcher utilities contribute to more informative and user-friendly error messages, aiding in quicker debugging. Furthermore, the unpacked size slightly increases, hinting at possible additions within the updated dependencies. These small changes can contribute to an improved testing experience and more stable development workflows.
All the vulnerabilities related to the version 24.5.0 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.
