CVE-2026-54889 Unsanitized URL schemes in MDEx Quill Delta output allow javascript: injection (XSS)

Improper Neutralization of Input During Web Page Generation XSS vulnerability in leandrocp mdex allows cross-site scripting via unsanitized URL schemes in Quill Delta output. 'Elixir.MDEx':todelta/2 converts Markdown into a Quill Delta. 'Elixir.MDEx.DeltaConverter':defaultconvertnode/3 in...

CVE-2026-54889

Summary: CVE-2026-54889 security issue in Elixir.MDEx.mdex Delta conversion path allows XSS via unsanitized URL schemes in Quill Delta output. The vulnerability arises when Elixir.MDEx.DeltaConverter.default_convert_node/3 copies the URL from link, wikilink, or image nodes into the Delta attribut...