PublicDateAtUSN: 2016-01-15
Candidate: CVE-2016-1908
PublicDate: 2017-04-11 18:59:00 UTC
References:
 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-1908
 https://lists.mindrot.org/pipermail/openssh-unix-dev/2016-January/034684.html
 https://thejh.net/written-stuff/openssh-6.8-xsecurity
 http://seclists.org/oss-sec/2016/q1/115
 https://ubuntu.com/security/notices/USN-2966-1
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.
Ubuntu-Description:
Notes:
 sbeattie> first patch needs to be applied before second one, which
 sbeattie> addresses the issue
 mdeslaur> contrary to release not, not fixed in 7.1p2:
 mdeslaur> http://lists.mindrot.org/pipermail/openssh-unix-dev/2016-January/034684.html
Bugs:
 https://bugzilla.redhat.com/show_bug.cgi?id=1298741
Priority: low
Discovered-by: Thomas Hoger
Assigned-to: mdeslaur
CVSS:
 nvd: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H [9.8 CRITICAL]

Patches_openssh:
 upstream: https://anongit.mindrot.org/openssh.git/commit/?id=f98a09cacff7baad8748c9aa217afd155a4d493f
 upstream: https://anongit.mindrot.org/openssh.git/commit/?id=ed4ce82dbfa8a3a3c8ea6fa0db113c71e234416c
upstream_openssh: released (7.2)
precise_openssh: released (1:5.9p1-5ubuntu1.9)
precise/esm_openssh: released (1:5.9p1-5ubuntu1.9)
trusty_openssh: released (1:6.6p1-2ubuntu2.7)
trusty/esm_openssh: released (1:6.6p1-2ubuntu2.7)
vivid_openssh: ignored (reached end-of-life)
vivid/stable-phone-overlay_openssh: ignored (reached end-of-life)
vivid/ubuntu-core_openssh: ignored (reached end-of-life)
wily_openssh: released (1:6.9p1-2ubuntu0.2)
xenial_openssh: not-affected (1:7.2p2-4)
esm-infra/xenial_openssh: not-affected (1:7.2p2-4)
yakkety_openssh: not-affected (1:7.2p2-5)
zesty_openssh: not-affected (1:7.2p2-5)
devel_openssh: not-affected (1:7.2p2-5)