Breaking out of chroot

From: Måns Rullgård (mru_at_users.sourceforge.net)
Date: 08/25/03 

Date: Mon, 25 Aug 2003 17:36:14 +0200

Lew.Pitcher@td.com (Lew Pitcher) writes:

>>> How do you get out of a chroot ?
>>
>>First, you need to gain root access.
>
> OK, Måns, Two things:
> 1. How do you gain root access? Especially while in a chroot jail?

Presumably through some bug in a program. You will object this is
supposed to be impossible, but it is supposed to be equally impossible
to gain root privileges outside of a chroot. If that were true, why
would we bother with chroot in the first place? Since exploits
obviously exist, what is to prevent them from existing inside the
chroot. Admittedly, the risk of having a buggy program inside the
chroot is smaller, since there are typically less programs there, and
putting SUID root programs in there wouldn't be very wise. Still,
there could be kernel bugs, and these are always present.

> 2. So, you're not saying that a chroot jail is escapable /on it's own/.
> You're saying that a chroot jail is escapable if you can break other
> security measures while in a chroot jail.

Well, wasn't the point of the chroot jail to protect the system, even
if security is broken inside? I only showed that chroot is useless
for this purpose. 

-- 
Måns Rullgård
mru@users.sf.net

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