1. Ubuntu Security Notices
  2. USN-2912-1

USN-2912-1: libssh vulnerabilities

Publication date

23 February 2016

Overview

Several security issues were fixed in libssh.

Releases

Packages

  • libssh - A tiny C SSH library

Details

Mariusz Ziulek discovered that libssh incorrectly handled certain packets.
A remote attacker could possibly use this issue to cause libssh to crash,
resulting in a denial of service.
(CVE-2015-3146)

Aris Adamantiadis discovered that libssh incorrectly generated ephemeral
secret keys of 128 bits instead of the recommended 1024 or 2048 bits when
using the diffie-hellman-group1 and diffie-hellman-group14 methods. If a
remote attacker were able to perform a machine-in-the-middle attack, this flaw
could be exploited to view sensitive information. (CVE-2016-0739)

Mariusz Ziulek discovered that libssh incorrectly handled certain packets.
A remote attacker could possibly use this issue to cause libssh to crash,
resulting in a denial of service.
(CVE-2015-3146)

Aris Adamantiadis discovered that libssh incorrectly generated ephemeral
secret keys of 128 bits instead of the recommended 1024 or 2048 bits when
using the diffie-hellman-group1 and diffie-hellman-group14 methods. If a
remote attacker were able to perform a machine-in-the-middle attack, this flaw
could be exploited to view sensitive information. (CVE-2016-0739)

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
15.10 wily libssh-4 –  0.6.3-3ubuntu3.2
14.04 trusty libssh-4 –  0.6.1-0ubuntu3.3
12.04 precise libssh-4 –  0.5.2-1ubuntu0.12.04.6

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Get Ubuntu Pro

References

Have additional questions?

Talk to a member of the team ›