=========================================================================Ubuntu Security Notice USN-3774-1
October 01, 2018

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

- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

strongSwan could be made to crash or run programs if it received specially
crafted network traffic.

Software Description:
- strongswan: IPsec VPN solution

Details:

It was discovered that strongSwan incorrectly handled signature validation
in the gmp plugin. A remote attacker could use this issue to cause
strongSwan to crash, resulting in a denial of service, or possibly execute
arbitrary code.

Update instructions:

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

Ubuntu 18.04 LTS:
  libstrongswan                   5.6.2-1ubuntu2.3
  strongswan                      5.6.2-1ubuntu2.3

Ubuntu 16.04 LTS:
  libstrongswan                   5.3.5-1ubuntu3.8
  strongswan                      5.3.5-1ubuntu3.8

Ubuntu 14.04 LTS:
  libstrongswan                   5.1.2-0ubuntu2.11
  strongswan                      5.1.2-0ubuntu2.11

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

References:
  https://ubuntu.com/security/notices/USN-3774-1
  CVE-2018-17540

Package Information:
  https://launchpad.net/ubuntu/+source/strongswan/5.6.2-1ubuntu2.3
  https://launchpad.net/ubuntu/+source/strongswan/5.3.5-1ubuntu3.8
  https://launchpad.net/ubuntu/+source/strongswan/5.1.2-0ubuntu2.11