@babel/runtime version 7.5.5 represents a minor update over the previous stable release, 7.5.4, offering subtle enhancements and refinements crucial for Babel-powered JavaScript projects. Both versions serve as Babel's modular runtime helpers, fundamentally supporting compiled code with necessary polyfills and utility functions to ensure cross-environment compatibility, especially when targeting older browsers or JavaScript runtimes.
The core dependencies remain consistent, with both relying on regenerator-runtime version ^0.13.2 for generator function support. However, the key difference lies in the developer dependencies; version 7.5.5 utilizes @babel/helpers version 7.5.5, increased from 7.5.4 in the prior release. This suggests potential updates or fixes in the helper functions that Babel uses internally during the transpilation process.
From a developer's perspective, while the dependency bump might seem minor, it's important to upgrade to the latest @babel/runtime release because each version may contain bug fixes, performance improvements, or subtle adjustments to the generated code that can positively impact application stability and efficiency. The increase in unpacked size from 88000 to 89155 suggests the addition of new helpers or modifications to existing ones. Furthermore, version 7.5.5 contains a minimal increase (2) the file count within the package. Therefore, upgrading projects using Babel is recommended to ensure they are running on the most up-to-date and optimized runtime environment.
All the vulnerabilities related to the version 7.5.5 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.