Email notification templates rendered the comment HTML via text/template,
so the store-level UGC sanitizer's permitted <a> and <img> tags reached
the email body verbatim. An authenticated user could plant phishing links
and remote tracking pixels in notification emails sent from the legitimate
remark42 address.
Switch notify to html/template (auto-escaping every non-HTML field) and
add a stricter email-only bluemonday policy that drops <a> and <img> while
keeping basic text formatting; the sanitized comment HTML is passed as
template.HTML. Add regression tests asserting links and images are stripped
while anchor text and formatting survive.
Dmitry VerkhoturovandUmputun
3e18681ca7