Same-origin protections for the PDF viewer can be bypassed, allowing a malicious site to intercept messages meant for the viewer. This could allow the site to retrieve PDF files restricted to viewing by an authenticated user on a third-party website. This vulnerability affects Firefox ESR < 52.8 and Firefox < 60.
- https://bugzilla.mozilla.org/show_bug.cgi?id=1449898
- https://github.com/ARPSyndicate/cvemon