Comment 2 for bug 1936299

Could you explain the exact meaning of disabling the sandboxing? I'm not getting it.
yes, _apt user has read access. can read all files

root@ip-10-0-0-144:/etc/apt/trusted.gpg.d# ls -l *
-rw-r--r-- 1 root root 2796 Mar 29 14:33 ubuntu-keyring-2012-archive.gpg
-rw-r--r-- 1 root root 2794 Mar 29 14:33 ubuntu-keyring-2012-cdimage.gpg
-rw-r--r-- 1 root root 1733 Mar 29 14:33 ubuntu-keyring-2018-archive.gpg
root@ip-10-0-0-144:/etc/apt/trusted.gpg.d# ls -l /etc/apt/trusted.gpg
-rw-r--r-- 1 root root 40254 Jul 15 07:26 /etc/apt/trusted.gpg
root@ip-10-0-0-144:/etc/apt/trusted.gpg.d#

It's a serious issue please help if anyone faced this issue.