Re: ptrace allows you to read -r files

From: Andrew Griffiths (andrewg@tasmail.com)
Date: Tue Feb 05 2002 - 05:12:01 EST


G'day,

After talking to some people, they confirm it is known, but what is the point of -r'ing binaries it if it can be read?

While it may not be a direct security threat, being able to look inside an otherwise unreadable binary can be a problem, for example, seeing if it is working or not, or possibly got entries for format strings.

Also some programs have a secret value inside them they use for authenication with remote clients. (Possibly Q by mixter @ mixter.warrior2k.com rings a bell).

While I guess there is no standard for ptrace, what do the other operating systems do? I've been told freebsd won't allow you to ptrace() a non-readable binary, but unable to confirm it myself.

On Monday, February 04, 2002 at 10:06:28 PM, Daniel Jacobowitz wrote:

> On Tue, Feb 05, 2002 at 11:33:32AM +1100, Andrew Griffiths wrote:
> > For those who want some demo code, you can find it at http://203.39.161.186/readbin.tgz.
>>
> I think this is just 'known'. Note that it isn't a security problem
> otherwise; you'll find that the setuid application does not setuid if
> it is ptraced. On 2.4.17 at least.
>
>

--
www.tasmail.com

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