Home / vulnerabilities Ubuntu Security Notice USN-2710-2
Posted on 19 August 2015
Source : packetstormsecurity.org Link
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Ubuntu Security Notice USN-2710-2
August 18, 2015
openssh regression
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A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 15.04
- Ubuntu 14.04 LTS
- Ubuntu 12.04 LTS
Summary:
USN-2710-1 introduced a regression in OpenSSH.
Software Description:
- openssh: secure shell (SSH) for secure access to remote machines
Details:
USN-2710-1 fixed vulnerabilities in OpenSSH. The upstream fix for
CVE-2015-5600 caused a regression resulting in random authentication
failures in non-default configurations. This update fixes the problem.
Original advisory details:
Moritz Jodeit discovered that OpenSSH incorrectly handled usernames when
using PAM authentication. If an additional vulnerability were discovered in
the OpenSSH unprivileged child process, this issue could allow a remote
attacker to perform user impersonation. (CVE number pending)
Moritz Jodeit discovered that OpenSSH incorrectly handled context memory
when using PAM authentication. If an additional vulnerability were
discovered in the OpenSSH unprivileged child process, this issue could
allow a remote attacker to bypass authentication or possibly execute
arbitrary code. (CVE number pending)
Jann Horn discovered that OpenSSH incorrectly handled time windows for
X connections. A remote attacker could use this issue to bypass certain
access restrictions. (CVE-2015-5352)
It was discovered that OpenSSH incorrectly handled keyboard-interactive
authentication. In a non-default configuration, a remote attacker could
possibly use this issue to perform a brute-force password attack.
(CVE-2015-5600)
Update instructions:
The problem can be corrected by updating your system to the following
package versions:
Ubuntu 15.04:
openssh-server 1:6.7p1-5ubuntu1.3
Ubuntu 14.04 LTS:
openssh-server 1:6.6p1-2ubuntu2.3
Ubuntu 12.04 LTS:
openssh-server 1:5.9p1-5ubuntu1.7
In general, a standard system update will make all the necessary changes.
References:
http://www.ubuntu.com/usn/usn-2710-2
http://www.ubuntu.com/usn/usn-2710-1
https://launchpad.net/bugs/1485719
Package Information:
https://launchpad.net/ubuntu/+source/openssh/1:6.7p1-5ubuntu1.3
https://launchpad.net/ubuntu/+source/openssh/1:6.6p1-2ubuntu2.3
https://launchpad.net/ubuntu/+source/openssh/1:5.9p1-5ubuntu1.7