CVE-2018-5108

A Blob URL can violate origin attribute segregation, allowing it to be
accessed from a private browsing tab and for data to be passed between the
private browsing tab and a normal tab. This could allow for the leaking of
private information specific to the private browsing context. This issue is
mitigated by the requirement that the user enter the Blob URL manually in
order for the access violation to occur. This vulnerability affects Firefox
< 58.