Description of problem:
My F9 system got hacked via SSH login of root. Admittedly root had a weak
password, but previously releases of Fedora/sshd disallowed root login by
default. Dictionary search allowed root login over SSH even though
/etc/ssh/sshd_config had #PermitRootLogin commented out. I had to explicitly set
PermitRootLogin no to stop root login. This is a changed in default behavior.
I was hacked before I had setup /etc/hosts.allow and /etc/hosts.deny to limit
system exposure to just a few outside systems.
Hacker was from domain ending with .ro. Created mysql and test logins. D/l a
file called "Diana.jpg" that was a zip file into /dev/shm. Contained a ssh-scan
executable that touched every binary on system /bin and /usr/bin attaching some
trojan. By the time it was caught there were 100 processes of this ssh-scan and
the network light on the computer was clicking away. Likely d/l all my files
for further scan. Had to do a full reinstall of F9.
Version-Release number of selected component (if applicable):
easily. Ensure #PermitRootLogin is commented out in sshd_config. Try it.
Steps to Reproduce:
Root login was never disallowed by default in Fedora/RHEL.
*** This bug has been marked as a duplicate of 89216 ***