Control: tags -1 confirmed
El 12/09/18 a las 10:36, Salvatore Bonaccorso escribió:
> Source: openssh
> Version: 1:6.7p1-5+deb8u6
> Severity: normal
>
> Hi
>
> DLA-1500-1 introduced the following regression: In cases where
> ForwardX11 is enabled, say globally for all via ssh_config, or via
> command line switch, but no DISPLAY is set (e.g. in cronjob), then newly
> a
>
> > DISPLAY "(null)" invalid; disabling X11 forwarding
>
> is issued.
>
> root@jessie-amd64:~# unset DISPLAY
> root@jessie-amd64:~# ssh -X root@localhost uname -a
> DISPLAY "(null)" invalid; disabling X11 forwarding
> Linux jessie-amd64 3.16.0-6-amd64 #1 SMP Debian 3.16.57-2 (2018-07-14) x86_64
> GNU/Linux
> root@jessie-amd64:~#
>
> Downgrading to 1:6.7p1-5+deb8u5 fixes the problem:
>
> root@jessie-amd64:~# unset DISPLAY
> root@jessie-amd64:~# ssh -X root@localhost uname -a
> Linux jessie-amd64 3.16.0-6-amd64 #1 SMP Debian 3.16.57-2 (2018-07-14) x86_64
> GNU/Linux
> root@jessie-amd64:~#
>
> This seem to be a specific regression in 1:6.7p1-5+deb8u6, the behaviour is
> not seen on
> either unstable (1:7.8p1-1) or stretch (1:7.4p1-10+deb9u4), so maybe
> one of the adressed issues misses a prerequisite commit?
Taking a quick look at it, I suppose the bug relates to the
CVE-2016-1908 fix.
For the record, the bug is also present in ubuntu 14.04 (trusty), where I took
the relevant patches from:
root@ubuntu-trusty:/# unset DISPLAY ; ssh -X ubuntu@localhost uname -a
DISPLAY "(null)" invalid; disabling X11 forwarding
Linux ubuntu-trusty 4.17.0-3-amd64 #1 SMP Debian 4.17.17-1 (2018-08-18) x86_64
x86_64 x86_64 GNU/Linux
root@ubuntu-trusty:/# unset DISPLAY ; ssh ubuntu@localhost uname -a
Linux ubuntu-trusty 4.17.0-3-amd64 #1 SMP Debian 4.17.17-1 (2018-08-18) x86_64
x86_64 x86_64 GNU/Linux
Thanks for your report! I will fix it ASAP.
cheers,
-- S
signature.asc
Description: PGP signature