CVE-2020-11051: Improper Neutralization of Input During Web Page Generation

In Wiki.js before 2.3.81, there is a stored XSS in the Markdown editor. An editor with write access to a page, using the Markdown editor, could inject an XSS payload into the content. If another editor (with write access as well) load the same page into the Markdown editor, the XSS payload will be executed as part of the preview panel. The rendered result does not contain the XSS payload as it is stripped by the HTML Sanitization security module. This vulnerability only impacts editors loading the malicious page in the Markdown editor. This has been patched in 2.3.81.