@babel/runtime version 7.16.3 represents a minor update to the popular Babel runtime library, building upon the previous stable version 7.16.0. Both versions provide essential modular runtime helpers necessary for executing code transformed by Babel, ensuring compatibility across different JavaScript environments. Key features such as support for regenerator-runtime (version ^0.13.4) remain consistent, indicating a focus on maintaining core functionality related to async/await and generator functions.
The newer version, 7.16.3, features a slightly reduced unpacked size (149256 bytes compared to 152951 bytes) and file count (187 files compared to 196 files). This suggests optimizations and refinements in the codebase, potentially leading to slightly improved performance or reduced bundle sizes for applications relying on @babel/runtime. While the core functionality remains largely the same, developers might find the 7.16.3 version beneficial for marginal gains in efficiency. The release date difference indicates that version 7.16.3 incorporates more recent patches and improvements up to November 9, 2021, compared to October 29, 2021, for version 7.16.0. Users are encouraged to update to the latest version as a best practice to leverage the newest optimizations and bug fixes, ensuring a more stable and performant runtime environment for their transpiled JavaScript code.
All the vulnerabilities related to the version 7.16.3 of the package
Babel has inefficient RegExp complexity in generated code with .replace when transpiling named capturing groups
When using Babel to compile regular expression named capturing groups, Babel will generate a polyfill for the .replace method that has quadratic complexity on some specific replacement pattern strings (i.e. the second argument passed to .replace).
Your generated code is vulnerable if all the following conditions are true:
.replace method on a regular expression that contains named capturing groups.replaceIf you are using @babel/preset-env with the targets option, the transform that injects the vulnerable code is automatically enabled if:
You can verify what transforms @babel/preset-env is using by enabling the debug option.
This problem has been fixed in @babel/helpers and @babel/runtime 7.26.10 and 8.0.0-alpha.17, please upgrade. It's likely that you do not directly depend on @babel/helpers, and instead you depend on @babel/core (which itself depends on @babel/helpers). Upgrading to @babel/core 7.26.10 is not required, but it guarantees that you are on a new enough @babel/helpers version.
Please note that just updating your Babel dependencies is not enough: you will also need to re-compile your code.
If you are passing user-provided strings as the second argument of .replace on regular expressions that contain named capturing groups, validate the input and make sure it does not contain the substring $< if it's then not followed by > (possibly with other characters in between).
This vulnerability was reported and fixed in https://github.com/babel/babel/pull/17173.