Trying to view the attachment at https://bugzilla.redhat.com/show_bug.cgi?id=1650362#c16 takes me to https://bugzilla-attachments.redhat.com/attachment.cgi?id=1512142&t=<elided> where I am unable to log in with key+otp or bugzilla password.
Other prodsec members report the same (pharvey, jhebden).
For those needing a workaround, python-bugzilla / pybugz can still download attachments using the xmlrpc interface.
Note the in browser feature has been turned off for now, so clicking an attachment will revert to the old download it behavior.
It appears this is a DNS related issue which is being pursued.
Verified on QA server
*** Bug 1669734 has been marked as a duplicate of this bug. ***
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