Re: [rfc] change default setuid permissions from 4755 to 4711

On Wed, Aug 03, Mike Frysinger wrote:

> > Hint: if for example one of shadow setuid tools will have known security
> > bug. How do think .. how many seconds intruder will stop for checkin is
> > attacked binary is readable or not ? (before runing exploit) and/or is
> > in this case removing read atrubutes will help or not ?
> 
> i never said that obscuring the data would protect the binaries.  it will 
> simply make it harder for the cracker (depending on the attack vector of 
> course) to exploit the vulnerability (whatever it may be).

This may be a dream of you, but has nothing to do with reality.

> a readable setuid  binary can be copied to a local directory or machine for analysis with 
> gdb/whatever to figure out the exact parameters needed for a successful 
> attack. 

And if he cannot copy it, he extract it from the installation media
or recompile it. Does not make a real difference.

> why export this information to all users if restricting it makes no difference 
> to the functionality ?  on binary-based distros such as 
> Debian/Redhat/SuSe/etc...  this changes nothing since an attacker can simply 
> grab the package from somewhere else, but on source based systems such as 
> Gentoo/Sorcerer/ROCK/etc... the binaries in use are not available anywhere 
> else for analysis.

You are wrong. If I have the same sources and compiler, the result
will be exactly the same. I don't need a binary package.

  Thorsten
-- 
Thorsten Kukuk         http://www.suse.de/~kukuk/      [email protected]
SUSE LINUX Products GmbH       Maxfeldstr. 5       D-90409 Nuernberg
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