A member of the Plone site could set javascript in the home_page
property of their profile, and have this executed when a visitor clicks the home page link on the author page.
github.com/plone/Products.CMFPlone
github.com/plone/Products.CMFPlone/commit/05a943ecbcdda56bacc93b55c9e2e908d8a7dfab
github.com/plone/Products.CMFPlone/commit/0e50e1e67ea3b6d3187f78cb1a1628081f654d3b
github.com/plone/Products.CMFPlone/commit/236b62b756ff46a92783b3897e717dfb15eb07d8
github.com/plone/Products.CMFPlone/commit/7db5b2c8fb684055987b8c4fdedc29289bd26373
github.com/plone/Products.CMFPlone/issues/2232
github.com/plone/Products.CMFPlone/pull/2233
github.com/plone/Products.CMFPlone/pull/2234
github.com/plone/Products.CMFPlone/pull/2235
github.com/plone/Products.CMFPlone/pull/2236
nvd.nist.gov/vuln/detail/CVE-2017-1000482
plone.org/security/hotfix/20171128/xss-using-the-home_page-member-property