@babel/runtime is a crucial package for Babel users, providing modular runtime helpers that enable the use of modern JavaScript features in environments where they are not natively supported. Analyzing versions 7.17.7 and 7.17.2 reveals subtle but potentially important differences for developers. Both versions maintain the same core description, license (MIT), source code repository on GitHub, and dependency on regenerator-runtime (^0.13.4), indicating a stable base. The key difference lies in the unpacked size of the package. While version 7.17.2 has an unpacked size of 170106 bytes, version 7.17.7 comes in slightly larger at 170180 bytes. This ~75 bytes increase likely indicates bug fixes, performance improvements or potentially new helper functions added between the releases. Both versions contain 191 files. The release dates also show a clear update timeline, with 7.17.2 released in February 2022 and 7.17.7 in March 2022. For developers, upgrading to the latest version (@babel/runtime 7.17.7) is generally recommended to benefit from the latest optimizations and fixes, ensuring smoother execution of Babel-compiled code. Monitoring changelogs associated with these minor version bumps is essential to understand the specific changes and their impact on your projects.
All the vulnerabilities related to the version 7.17.7 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.