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Alerts This Week
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Ubuntu 15.04: USN-2710-2 High Severity OpenSSH Authentication Issue

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Calendar Grey August 18, 2015
Scroller Ubuntu
Ubuntu Security Alert USN-2710-2 addresses issues with OpenSSH, correcting a regression and several authentication vulnerabilities that affect various versions.
USN-2710-1 introduced a regression in OpenSSH.

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. (CV...

Read the Full Advisory

Topics%20covered

Topics Covered

security advisory security update high severity Ubuntu authentication issue OpenSSH regression fix

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

https://ubuntu.com/security/notices/USN-2710-1

https://bugs.launchpad.net/ubuntu/+source/openssh/+bug/1485719

Severity
important
Lowest
Low
Medium
High
Critical

August 18, 2015

Topics%20covered

Topics Covered

security advisory security update high severity Ubuntu authentication issue OpenSSH regression fix

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

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