< 2.19.1 contains 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.
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The Loofah maintainers have evaluated this as High Severity 7.5 (CVSS3.1).
This vulnerability was responsibly reported by @ooooooo-q (https://github.com/ooooooo-q).