The cr_parser_parse_selector_core function in cr-parser.c in libcroco 0.6.12 allows remote attackers to cause a denial of service (infinite loop and CPU consumption) via a crafted CSS file.
https://bugzilla.gnome.org/show_bug.cgi?id=782649
http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00043.html