@babel/runtime provides modular runtime helpers for Babel transformations, enabling developers to use modern JavaScript features in older environments. Comparing versions 7.12.17 and 7.12.18, while seemingly incremental, reveals notable differences. Both versions maintain the same core purpose, license (MIT), author, and dependency on regenerator-runtime (version ^0.13.4), crucial for async/await support. Developers relying on async functions or generator functions continue to benefit from this dependency. The GitHub repository remains consistent, indicating the source code location for both versions.
The key discrepancies lie in the distribution (dist) metadata. Version 7.12.18 boasts a significantly larger file count (167 vs. 11) and unpacked size (113524 bytes vs. 15587 bytes) compared to 7.12.17. This hints at added functionalities, expanded support for specific Babel transformations, or more comprehensive polyfilling in the newer version. Developers should investigate the changelog of Babel itself to fully understand the nature of these additions. The release dates are also close, with 7.12.18 being released shortly after 7.12.17. For developers, choosing between versions depends on their specific Babel configuration and target environments. While 7.12.18 may offer enhanced support, the increased size could impact bundle sizes. Checking babel's changelog related to these versions is advisable.
All the vulnerabilities related to the version 7.12.18 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.