On 30/12/14 22:07, Valeri Galtsev wrote:
I have that vague feeling that what I'm about to say will probably be declared wrong... Still. From the very beginning I do not consider SELinux adding to the security of the system. How can it if it can be turned off on the fly? On the other hand, it adds hundreds of thousands of lines to kernel code which does exactly opposite: deteriorates security by potentially introducing bugs. I discovered at some point that there are other people out there who share this opinion ;-)
So, my question is: can someone design attack scenario which would be successful if it were not for SELinux, and which is thwarted by SELinux. Note that the fact that script kiddie just forgot to put as a first line
/usr/sbin/setenforce 0
doesn't make such example a solid case pro SELinux for me.
Thanks a lot for your insight! (Always hoping to learn ;-)
Disabling SELinux requires root privileges at which point most all security implimentations are pretty useless.
Firewalls add much code to the kernel and can also be "turned off on the fly" by any "script kiddie" with root privileges. Should we discount them too?
IMHO your arguments are weak with bad examples. The questions you should be asking is how effective would SELinux be in preventing an initial remote exploit, or preventing an attacker gaining further escalation of privileges once they have gained access to the system.
In answer to your question, you will find lots of good real life examples in Dans' blog here: