=========================================================================Ubuntu Security Notice USN-4327-1
April 09, 2020

libssh vulnerability
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 19.10
- Ubuntu 18.04 LTS

Summary:

libssh could be made to crash if it received specially crafted network
traffic.

Software Description:
- libssh: A tiny C SSH library

Details:

Yasheng Yang discovered that libssh incorrectly handled AES-CTR ciphers. A
remote attacker could possibly use this issue to cause libssh to crash,
resulting in a denial of service.

Update instructions:

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

Ubuntu 19.10:
  libssh-4                        0.9.0-1ubuntu1.4

Ubuntu 18.04 LTS:
  libssh-4                        0.8.0~20170825.94fa1e38-1ubuntu0.6

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

References:
  https://ubuntu.com/security/notices/USN-4327-1
  CVE-2020-1730

Package Information:
  https://launchpad.net/ubuntu/+source/libssh/0.9.0-1ubuntu1.4
  https://launchpad.net/ubuntu/+source/libssh/0.8.0~20170825.94fa1e38-1ubuntu0.6