Indeed. PuTTY 0.62 and earlier had a habit of generating slightly short keys sometimes.
This is unlikely to change in OpenSSH - the minimum key size is only likely to increase over time. I'd strongly suggest just generating a 2048-bit key, since SSH keys are usually pretty easy to roll over. ** Changed in: openssh (Ubuntu) Status: Confirmed => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1756031 Title: openssh-server doesn't accept aes256-cbc key To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/openssh/+bug/1756031/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs