The remote Confluence server is affected by a stored cross-site scripting (XSS) vulnerability.
Versions of Confluence 5.4.x prior to 5.4.2 contain a flaw that allows a stored XSS attack. This flaw exists because the 'Share a link' feature does not validate input to topics in a new dialog before returning it to users. This may allow an authenticated remote attacker to create a specially crafted request that would execute arbitrary script code in a user's browser session within the trust relationship between their browser and the server.
Upgrade to Confluence 5.4.x version 5.4.2 or later.