Julian, thanks for your patience. I'm not able to offer a shell on the affected machine, so debugging this is just going to have to go at a snail's pace.
I read strace and ltrace logs from both 1.2.12-ish and 1.2.15 apt packages and narrowed it down to /usr/bin/apt-key. When I use the /usr/bin/apt-key from apt_1.2.12~ubuntu16.04.1_amd64.deb (but everything else from 1.2.15 packaging) my apt-get update runs as I expect. I'll attach the diff between the two (NOT A FIX). Thanks ** Patch added: "apt-key.patch" https://bugs.launchpad.net/ubuntu/+source/apt/+bug/1642386/+attachment/4779725/+files/apt-key.patch -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1642386 Title: At least one invalid signature was encountered. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apt/+bug/1642386/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
