Hi. On Fri, Sep 21, 2018 at 08:55:21AM -0400, Henning Follmann wrote: > On Fri, Sep 21, 2018 at 08:34:50AM +0530, Subhadip Ghosh wrote: > > Hi, > > > > I am using Debian and the recently I learned that a standard Debian > > installation allows all 3 types of traffics especially incoming by default. > > I know I can easily use iptables to tighten the rules but I wanted to know > > the reasons behind the choice of this default behaviour and if it makes the > > system more vulnerable? I tried searching on the Internet but did not get > > any satisfactory explanation. It will be helpful if anybody knows the > > answers to my questions or can redirect me to a helpful document. > > > > The answer is easy. Because Debian is awesome (TM). So are most other > distributions.
Hear, hear. > Run a netstat -t -l and you will see there is nothing listening. So what is > the point of running a firewall? The point is to be a good netizen, as always. By running any sane kind of packet filter you're avoiding participating in TCP RST attack. > By default no services (ipp might be the one exception) are running and > listening. Portmapper does - tcp 111. Reco