Comment 9 for bug 1966591

Verification for Focal:

First, verifying that the bug manifests with the current package:

# apt policy openssh-client
openssh-client:
  Installed: 1:8.2p1-4ubuntu0.4
  Candidate: 1:8.2p1-4ubuntu0.4
  Version table:
 *** 1:8.2p1-4ubuntu0.4 500
        500 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     1:8.2p1-4ubuntu0.2 500
        500 http://security.ubuntu.com/ubuntu focal-security/main amd64 Packages
     1:8.2p1-4 500
        500 http://archive.ubuntu.com/ubuntu focal/main amd64 Packages
# ssh-keygen -R github.com -f test_known_hosts
# Host github.com found: line 1
# Host github.com found: line 2
# Host github.com found: line 3
test_known_hosts updated.
Original contents retained as test_known_hosts.old
# stat test_known_hosts | grep ^Access
Access: (0600/-rw-------) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2022-04-13 21:54:40.698183232 +0000

Now, enabling -proposed and verifying that the new package fixes the bug:

# apt policy openssh-client
openssh-client:
  Installed: 1:8.2p1-4ubuntu0.5
  Candidate: 1:8.2p1-4ubuntu0.5
  Version table:
 *** 1:8.2p1-4ubuntu0.5 500
        500 http://archive.ubuntu.com/ubuntu focal-proposed/main amd64 Packages
        100 /var/lib/dpkg/status
     1:8.2p1-4ubuntu0.4 500
        500 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages
     1:8.2p1-4ubuntu0.2 500
        500 http://security.ubuntu.com/ubuntu focal-security/main amd64 Packages
     1:8.2p1-4 500
        500 http://archive.ubuntu.com/ubuntu focal/main amd64 Packages
# ssh-keygen -R github.com -f test_known_hosts
# Host github.com found: line 1
# Host github.com found: line 2
# Host github.com found: line 3
test_known_hosts updated.
Original contents retained as test_known_hosts.old
# stat test_known_hosts | grep ^Access
Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2022-04-13 21:57:25.676987718 +0000

The bug has been fixed.