Package        : openssh
Version        : 1:6.7p1-5+deb8u7
Debian Bug     : 908652


The security update of OpenSSH announced as DLA 1500-1 introduced a bug in
openssh-client: when X11 forwarding is enabled (via system-wide
configuration in ssh_config or via -X command line switch), but no DISPLAY
is set, the client produces a "DISPLAY "(null)" invalid; disabling X11
forwarding" warning. These bug was introduced by the patch set to fix the
CVE-2016-1908 issue. For reference, the following is the relevant section
of the original announcement:

CVE-2016-1908

    OpenSSH mishandled untrusted X11 forwarding when the X server disables
    the SECURITY extension. Untrusted connections could obtain trusted X11
    forwarding privileges. Reported by Thomas Hoger.

For Debian 8 "Jessie", this problem has been fixed in version
1:6.7p1-5+deb8u7.

We recommend that you upgrade your openssh packages.

Further information about Debian LTS security advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://wiki.debian.org/LTS

Debian LTS: DLA-1500-2: openssh regression update

September 12, 2018
The security update of OpenSSH announced as DLA 1500-1 introduced a bug in openssh-client: when X11 forwarding is enabled (via system-wide configuration in ssh_config or via -X com...

Summary

CVE-2016-1908

OpenSSH mishandled untrusted X11 forwarding when the X server disables
the SECURITY extension. Untrusted connections could obtain trusted X11
forwarding privileges. Reported by Thomas Hoger.

For Debian 8 "Jessie", this problem has been fixed in version
1:6.7p1-5+deb8u7.

We recommend that you upgrade your openssh packages.

Further information about Debian LTS security advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://wiki.debian.org/LTS


Severity
Package        : openssh
Version : 1:6.7p1-5+deb8u7
Debian Bug : 908652

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