Re: OT? Are chroots immune to buffer overflows?

From: Edwin Groothuis (edwin@mavetju.org)
Date: 05/22/02


Date: Wed, 22 May 2002 22:53:15 +1000
From: Edwin Groothuis <edwin@mavetju.org>
To: Jason Haar <Jason.Haar@trimble.co.nz>

On Wed, May 22, 2002 at 03:48:16PM +1200, Jason Haar wrote:
> [note: my question is WRT non-root chrooted jails - we all know about
> chroot'ing root processes!]
>
> Most buffer overflows I've seen attempt to infiltrate the system enough to
> run /bin/sh. In chroot'ed environments, /bin/sh doesn't (shouldn't!) exist -
> so they fail.
>
> Is it as simple as that? As 99.999% of the system binaries aren't available
> in the jail, can a buffer overflow ever work?

A buffer-overflow allows an attacker to execute any piece of code.
Most of the this it is the running of /bin/sh because it gives the
attacker the biggest playingfield, but it can be anything.

For example with a DNS server in a chrooted environment, it can be
told to unlink the named.conf. Not that the attacker can do anything
usefull with it then, but it does some damage.

Edwin

-- 
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Relevant Pages

  • buffer overflows
    ... Many advisories list the problem of buffer overflows which allow the ... attacker to run arbitrary code as a privileged user. ...
    (comp.security.misc)
  • Re: OT? Are chroots immune to buffer overflows?
    ... Jason Haar wrote: ... > Most buffer overflows I've seen attempt to infiltrate the system enough to ... > so they fail. ...
    (Vuln-Dev)
  • Re: [Lit.] Buffer overruns
    ... >> You are kidding, right? ... We are talking about buffer overflows. ... >> If the code in question does not have them, the attacker cannot ... > truly have no idea how to follow that prescription. ...
    (sci.crypt)
  • Re: unautherized access to unix systems?
    ... say the attacker has found an exploitable service. ... Can buffer overflows be programed in perl, ... anyone know a good tutorial on Buffer Overflows programmed in perl? ...
    (comp.security.unix)
  • Re: [Lit.] Buffer overruns
    ... Hank Oredson wrote: ... > You are kidding, right? ... We are talking about buffer overflows. ... > If the code in question does not have them, the attacker cannot ...
    (sci.crypt)