Ubuntu Security Notice USN-2966-1
9th May, 2016
openssh vulnerabilities
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 15.10
- Ubuntu 14.04 LTS
- Ubuntu 12.04 LTS
Summary
Several security issues were fixed in OpenSSH.
Software description
- openssh
– secure shell (SSH) for secure access to remote machines
Details
Shayan Sadigh discovered that OpenSSH incorrectly handled environment files
when the UseLogin feature is enabled. A local attacker could use this issue
to gain privileges. (CVE-2015-8325)
Ben Hawkes discovered that OpenSSH incorrectly handled certain network
traffic. A remote attacker could possibly use this issue to cause OpenSSH
to crash, resulting in a denial of service. This issue only applied to
Ubuntu 15.10. (CVE-2016-1907)
Thomas Hoger discovered that OpenSSH incorrectly handled untrusted X11
forwarding when the SECURITY extension is disabled. A connection configured
as being untrusted could get switched to trusted in certain scenarios,
contrary to expectations. (CVE-2016-1908)
It was discovered that OpenSSH incorrectly handled certain X11 forwarding
data. A remote authenticated attacker could possibly use this issue to
bypass certain intended command restrictions. (CVE-2016-3115)
Update instructions
The problem can be corrected by updating your system to the following
package version:
- Ubuntu 15.10:
-
openssh-server
1:6.9p1-2ubuntu0.2
- Ubuntu 14.04 LTS:
-
openssh-server
1:6.6p1-2ubuntu2.7
- Ubuntu 12.04 LTS:
-
openssh-server
1:5.9p1-5ubuntu1.9
To update your system, please follow these instructions:
https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system update will make all the necessary changes.