Crass : Large numeric exponents cause CPU and memory denial of service

Impact

Crass converts CSS scientific notation number values with unbounded exponentiation before it clamps the result to Float::MAX. Applications that use Crass to parse attacker-controlled CSS strings can be forced to spend disproportionate CPU and memory parsing a tiny input, possibly resulting in a crash.

Patches

This is fixed in Crass 1.0.7.

Related

• https://github.com/rubysec/ruby-advisory-db/blob/master/gems/crass/GHSA-6wmf-3r64-vcwv.yml