In LibSass prior to 3.5.5, functions inside ast.cpp for IMPLEMENT_AST_OPERATORS expansion allow attackers to cause a denial-of-service resulting from stack…

In LibSass prior to 3.5.5, functions inside ast.cpp for IMPLEMENT_AST_OPERATORS expansion allow attackers to cause a denial-of-service resulting from stack consumption via a crafted sass file, as demonstrated by recursive calls involving clone(), cloneChildren(), and copy().