Certain configurations of rails-html-sanitizer
< 1.4.4 use an inefficient regular expression that is susceptible to excessive backtracking when attempting to sanitize certain SVG attributes. This may lead to a denial of service through CPU resource consumption.
Upgrade to rails-html-sanitizer
The maintainers have evaluated this as High Severity 7.5 (CVSS3.1).
This vulnerability was responsibly reported by @ooooooo-q (https://github.com/ooooooo-q).