@babel/runtime version 7.13.8 introduces subtle yet potentially impactful changes compared to its predecessor, version 7.13.7. While both versions share the same core description as Babel's modular runtime helpers, dependency on regenerator-runtime (^0.13.4), MIT license, GitHub repository, and author, a closer examination reveals key differences. The most notable change lies in the unpacked size, with version 7.13.8 weighing in at 143,222 bytes, a slight decrease from version 7.13.7's 143,816 bytes. This suggests optimizations or minor code adjustments within the newer release, possibly related to performance enhancements or bug fixes. Additionally, the release date signifies that version 7.13.8 was published on February 26, 2021, approximately two days after version 7.13.7 (February 24, 2021).
For developers utilizing @babel/runtime, these small changes often translate to improved code generation and execution efficiency when using Babel to transpile modern JavaScript code. By staying up-to-date with the latest version, developers can benefit from potential bug fixes, performance improvements, and refinements to the runtime helpers that support asynchronous operations and other advanced language features. Carefully evaluating the release notes accompanying each version is recommended, as minimal adjustments could address specific edge cases or provide compatibility enhancements with different target environments. The number of files in the distributed package tarball has remained consistent between the two versions.
All the vulnerabilities related to the version 7.13.8 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.