Discourse is an option source discussion platform. Prior to version 2.8.14 on the stable
branch and version 3.0.0.beta16 on the beta
and tests-passed
branches, tag descriptions, which can be updated by moderators, can be used for cross-site scripting attacks. This vulnerability can lead to a full XSS on sites which have modified or disabled Discourse’s default Content Security Policy. Versions 2.8.14 and 3.0.0.beta16 contain a patch.