| Name | CVE-2016-1908 |
| Description | The client in OpenSSH before 7.2 mishandles failed cookie generation for untrusted X11 forwarding and relies on the local X11 server for access-control decisions, which allows remote X11 clients to trigger a fallback and obtain trusted X11 forwarding privileges by leveraging configuration issues on this X11 server, as demonstrated by lack of the SECURITY extension on this X11 server. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DLA-1500-1 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| openssh (PTS) | bullseye (security), bullseye | 1:8.4p1-5+deb11u3 | fixed |
| bookworm, bookworm (security) | 1:9.2p1-2+deb12u3 | fixed | |
| sid, trixie | 1:9.9p1-3 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| openssh | source | jessie | 1:6.7p1-5+deb8u6 | DLA-1500-1 | ||
| openssh | source | (unstable) | 1:7.2p1-1 |
[wheezy] - openssh <no-dsa> (Minor issue)
[squeeze] - openssh <no-dsa> (Minor issue)
Upstream commit: https://anongit.mindrot.org/openssh.git/commit/?id=ed4ce82dbfa8a3a3c8ea6fa0db113c71e234416c
which needs to be applied after: https://anongit.mindrot.org/openssh.git/commit/?id=f98a09cacff7baad8748c9aa217afd155a4d493f
Background information on X11 SECURITY extension and SSH: https://thejh.net/written-stuff/openssh-6.8-xsecurity
https://lists.mindrot.org/pipermail/openssh-unix-dev/2016-January/034684.html
Red Hat Bugzilla entry: https://bugzilla.redhat.com/show_bug.cgi?id=1298741
vulnerability is partly due to /etc/X11/Xsession.d/35x11-common_xhost-local introduced in x11-common in 1:7.6+9 (wheezy and up)
https://lists.debian.org/debian-lts/2016/01/msg00029.html
Upstream announce: http://www.openssh.com/txt/release-7.2