1. Ubuntu Security Notices
  2. USN-3061-1

USN-3061-1: OpenSSH vulnerabilities

Publication date

15 August 2016

Overview

Several security issues were fixed in OpenSSH.

Releases

Packages

  • openssh - secure shell (SSH) for secure access to remote machines

Details

Eddie Harari discovered that OpenSSH incorrectly handled password hashing
when authenticating non-existing users. A remote attacker could perform a
timing attack and enumerate valid users. (CVE-2016-6210)

Tomas Kuthan, Andres Rojas, and Javier Nieto discovered that OpenSSH did
not limit password lengths. A remote attacker could use this issue to cause
OpenSSH to consume resources, leading to a denial of service.
(CVE-2016-6515)

Eddie Harari discovered that OpenSSH incorrectly handled password hashing
when authenticating non-existing users. A remote attacker could perform a
timing attack and enumerate valid users. (CVE-2016-6210)

Tomas Kuthan, Andres Rojas, and Javier Nieto discovered that OpenSSH did
not limit password lengths. A remote attacker could use this issue to cause
OpenSSH to consume resources, leading to a denial of service.
(CVE-2016-6515)

Update instructions

In general, a standard system update will make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
16.04 xenial openssh-server –  1:7.2p2-4ubuntu2.1
14.04 trusty openssh-server –  1:6.6p1-2ubuntu2.8
12.04 precise openssh-server –  1:5.9p1-5ubuntu1.10

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References

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