[TriLUG] Re: Nagios plugin check_http segmentation fault - potential for buffer overflow?

[David McDowell]

oh, I forgot my nagios-plugins package version:
nagios-plugins-1.4.4-1.el4.rf from same DAG repo on CentOS 4.4

:)


On 11/22/06, David McDowell <turnpike420 at gmail.com> wrote:
> I am running nagios-2.5-1.el4.rf  version from DAG repo on CentOS 4.4.
>  I ran across this only b/c I forgot to setup my good username and
> password in my /etc/nagios/resources.cfg file for this plugin to use.
> Scenario 2 is a result of that *oops* if you fake the oops on the
> command line and is the important one to focus on.  Does this leave
> open the potential for a buffer overflow and if so, I suppose I should
> report it.  I wanted to share with others first for more input.
> Notice the 2nd part of Result 2 still returns green OK to nagios, this
> can't be by design is it?
>
> Scenario 1:  submit bad username and bad password
>
> [root at nagios plugins]# ./check_http -H 192.168.1.61 -S -a badfoo:badbar
> HTTP WARNING: HTTP/1.1 401 Authorization Required
>
> Result 1:  works as expected
>
> Scenario 2:  forget to setup the user argument resources in
> /etc/nagios/resource.cfg and then you get this:
>
> [root at nagios plugins]# ./check_http -H 192.168.1.61 -S -a :
> Segmentation fault
>
> Result 2:  uh oh, could this leave room for a buffer overflow attack?
> I'm not sure this should be segmentation faulting.  Also, "No Output!"
> is the message returned to nagios and the service is left green OK as
> if nothing is wrong with it.
>
> Scenario 3:  correctly setup /etc/nagios/resources.cfg with good
> username and password
>
> [root at nagios plugins]# ./check_http -H 192.168.1.61 -S -a goodfoo:goodbar
> HTTP OK HTTP/1.1 200 OK - 11174 bytes in 0.096 seconds
> |time=0.096014s;;;0.000000 size=11174B;;;0
>
> Result 3:  works as expected
>
>
> I hope I've included enough info.  If anyone has immediate direct
> contact with any of the nagios folks, this might be a good one to
> share with them right away.  If anyone else is so inclined, can you
> also reproduce this error?  I can reproduce this same error/results
> with nagios-2.4-1.el4.rf from DAG repo as well.
>
> thanks,
> David McD
>