I appreciate you bringing this to our attention, but (as shadow upstream maintainer) I'm going to join John in saying this should be wontfix.
Now if you want to change the subject to also making /etc/passwd 600, then as Alexander points out that may be doable and have merit. But just hiding the backup file doesn't make sense, and as it would require extra code in the already fiddly backup code in shadow, there is regression concern. ** Changed in: shadow (Ubuntu) Status: Confirmed => Won't Fix -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to shadow in Ubuntu. https://bugs.launchpad.net/bugs/1923262 Title: backup /etc/passwd- file should be mode 0600 Status in shadow package in Ubuntu: Won't Fix Bug description: CIS hardening benchmarks (6.1.6) suggest that the /etc/passwd- file should be mode 0600 (or more restrictive). However, this file is 0644 after it is created when the /etc/passwd file is modified. (Ie, a hardening script that creates a hardened system for initial use could change this mode, but it will go out of compliance the next time a backup file is made.) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/shadow/+bug/1923262/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp