Brandon's Blog

10/23/2007

That Pesky Password for www-data

Having a home server has been an educational experience.  And, between Debian’s sensible defaults and my own research and experience, I feel like I run a safe shop.

Last weekend I got portscanned on joey.  The scanner found my SSH port and started running a dictionary attack.  (Amazing what a real operating system’s logs will tell you!)  The scanner managed to login as an extremely unprivileged user (www-data, the user account under which Apache2 runs on Debian).  They were logged in for exactly 7 seconds.

The Apache2 user can barely even view files without asking permission, so the threat was less than nil.  However, I felt like refreshing the system just to make sure.

I have also now disabled SSH logins from external sources, which pretty much nips that issue in the bud.  But, I could re-open it without any concern.  I learned my lesson about passwords and exactly how many nefarious characters are really operating around the web.

I managed to get all essential services up and running last night, aside from forgetting to get the Dynamic DNS client running (which effectively makes the server inaccessible from the outside).  I need to tweak Samba (Windows-compatible file server) to have a shared directory again, but all in all things were done very quickly.

It’s not hard to administer a server like this, but I’m beginning to respect the need for constant vigilence on a much higher level.