Comment 12 for bug 1577926

This affected me as well, after upgrading a digital ocean VM from 14.04 to 16.04.1.

I straced the call, as well as using inotify tools to capture the temporary files created. An interesting line in the strace is:

[pid 2608] execve("/usr/bin/apt-key", ["/usr/bin/apt-key", "--quiet", "--readonly", "verify", "--status-fd", "3", "/tmp/apt.sig.CbTOUo", "/tmp/apt.data.rwmcWB"], [/* 25 vars */]) = -1 EPERM (Operation not permitted)

Can post the entire strace dump if people think it would be helpful. The apt.sig file was empty, whereas the apt.data file was 13k.