MDC is a tool to take regular Markdown and write documents interacting deeply with a Vue component. Prior to version 0.17.2, a remote script-inclusion / stored cross-site scripting vulnerability in @nuxtjs/mdc lets a Markdown author inject a `<base href="https://attacker.tld">` element. The `<base>` tag rewrites how all subsequent relative URLs are resolved, so an attacker can make the page load scripts, styles, or images from an external, attacker-controlled origin and execute arbitrary JavaScript in the site’s context. Version 0.17.2 contains a fix for the issue.
https://github.com/nuxt-modules/mdc/security/advisories/GHSA-cj6r-rrr9-fg82
https://github.com/nuxt-modules/mdc/commit/3657a5bf2326a73cd3d906f57149146a412b962a