[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: My sarge box has an IRC bot



On Fri, Jan 12, 2007 at 02:22:48PM +0100, Sven Arvidsson wrote:
> On Thu, 2007-01-11 at 18:52 -0500, Roberto C. Sanchez wrote:
> > Yup.  While that will thwart the most naïve of attacks, put a binary
> > (not a script) in there (something like ls works) and run this:
> > 
> > /lib/ld-linux.so.2 /tmp/ls
> 
> That is actually not possible if you have a recent linux kernel.
> 
What kernel?  I am running 2.6.17.

>         "Newer versions of the kernel do however handle the noexec flag
>         properly:
>         
>                angrist:/tmp# mount | grep /tmp
>                /dev/hda3 on /tmp type ext3 (rw,noexec,nosuid,nodev)
>                angrist:/tmp# ./date
>                bash: ./tmp: Permission denied 
>                angrist:/tmp# /lib/ld-linux.so.2 ./date 
>                ./date: error while loading shared libraries: ./date: failed to map segment 
>                from shared object: Operation not permitted"
> 
> http://www.debian.org/doc/manuals/securing-debian-howto/ch4.en.html#s4.10
> 
> There might still be an easy way around that of course.
> 
Probably so.

Regards,

-Roberto


-- 
Roberto C. Sanchez
http://people.connexer.com/~roberto
http://www.connexer.com

Attachment: signature.asc
Description: Digital signature


Reply to: