Stack overflow vulnerability in ast_selectors.cpp: in function Sass::ComplexSelector::has_placeholder in libsass:3.6.5-8-g210218, which can be exploited by attackers to cause a denial of service (DoS).Referenceshttps://github.com/sass/libsasshttps://drive.google.com/file/d/1j5fkPjWH9zQeTdO_4dMcZ-FpOBzP0MaI/https://github.com/sass/libsass/issues/3178
