connorskees grass UTF-8 Character raw_to_parse_error denial of service

Summary

A flaw has been found in connorskees grass up to 0.13.4. The affected element is the function grass_compiler::raw_to_parse_error of the component UTF-8 Character Handler. Executing a manipulation can lead to denial of service. The attack is restricted to local execution. The exploit has been published and may be used. In Issue #117 with similar structure the project maintainer explains: "DoS vulnerabilities are generally fine in Sass compilers -- they are trivially possible with recursive functions, infinite loops, nested mixins, etc. The description here is wrong. Compile time is not expected to be linear relative to the input, and the @extend algorithm is definitionally exponential."