Parsing and rendering of YouTube Oneboxes can be susceptible to XSS attacks. This vulnerability only affects sites which have modified or disabled Discourse's default Content Security Policy.
Patches
This issue is patched in the latest stable, beta and tests-passed versions of Discourse
Workarounds
Ensure that the Content Security Policy is enabled, and has not been modified in a way which would make it more vulnerable to XSS attacks.
Impact
Parsing and rendering of YouTube Oneboxes can be susceptible to XSS attacks. This vulnerability only affects sites which have modified or disabled Discourse's default Content Security Policy.
Patches
This issue is patched in the latest
stable,betaandtests-passedversions of DiscourseWorkarounds
Ensure that the Content Security Policy is enabled, and has not been modified in a way which would make it more vulnerable to XSS attacks.