Kramdown before 2.3.1 does not restrict Rouge formatters to the Rouge::Formatters namespace, and thus arbitrary classes can be instantiated.Referenceshttps://github.com/gettalong/kramdown/pull/708https://gitlab.com/gitlab-org/gitlab/-/commit/179329b5c3c118924fb242dc449d06b4ed6ccb66https://github.com/gettalong/kramdown/compare/REL_2_3_0...REL_2_3_1https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/S3BBLUIDCUUR3NEE4NJLOCCAV3ALQ3O6/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SYOLQKFL6IJCQLBXV34Z4TI4O54GESPR/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NJCJVYHPY6LNUFM6LYZIAUIYOMVT5QGV/https://www.debian.org/security/2021/dsa-4890
