Mounting filesystems with "noexec"

Borja Marcos borjamar at sarenet.es
Fri Sep 23 00:04:30 PDT 2005


> Instead of running "./script.sh" or "./script.pl" you just have to  
> type
> /bin/sh script.sh or /usr/bin/perl script.pl which gives pretty much
> everything you need when it comes to using exploits. In linux you  
> could
> also circumvent it by using /lib/ld.so exploit, but i'm not sure if  
> that
> is "fixed" now or not.

I'm well aware of this, obviously :-)

But, with TPE or without TPE, any command with a script language, be  
it a shell, Perl, Tcl, or whatever (even Java) should perform that  
check, which is not a good design practice.

That said, my point is this: the amount of damage you can do from a  
"native" program is greater than the damage you can achieve from a  
script language, afaik. At least a privilege escalation should be  
harder to obtain. I'm not sure about some languages such as Perl,  
though.

Of course, this is only one among a bigger set of security measures.




Borja.



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