[lettersanitizer] Improper handling of CSS at-rules in lettersanitizer

Impact

All versions of lettersanitizer below 1.0.2 are affected by a denial of service issue when processing a CSS at-rule @keyframes.

This package is depended on by react-letter, therefore everyone using react-letter is also at risk.

Patches

The problem has been patched in version 1.0.2.

Workarounds

There is no workaround besides upgrading.

References

The issue was originally reported in the react-letter repository: https://github.com/mat-sz/react-letter/issues/17

For more information

If you have any questions or comments about this advisory:

• Open an issue in lettersanitizer
• Email me at contact@matsz.dev

References

• https://github.com/mat-sz/lettersanitizer/security/advisories/GHSA-7r3r-gq8p-v9jj
• https://github.com/mat-sz/react-letter/issues/17
• https://github.com/mat-sz/lettersanitizer/commit/96d3dfe2ef0465d47324ed4d13e91ba0816a173f
• https://github.com/advisories/GHSA-7r3r-gq8p-v9jj