HAproxy would allow unintended access if ii received specially crafted HTTP request.

==========================================================================
Ubuntu Security Notice USN-4174-1
November 05, 2019

haproxy vulnerability
==========================================================================

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

- Ubuntu 19.10
- Ubuntu 19.04
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

HAproxy would allow unintended access if ii received specially crafted
HTTP request.

Software Description:
- haproxy: fast and reliable load balancing reverse proxy

Details:

It was discovered that HAproxy incorrectly handled certain HTTP requests.
An attacker could possibly use this issue to a privilege escalation
(Request Smuggling).

Update instructions:

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

Ubuntu 19.10:
  haproxy                         2.0.5-1ubuntu0.2

Ubuntu 19.04:
  haproxy                         1.8.19-1ubuntu1.2

Ubuntu 18.04 LTS:
  haproxy                         1.8.8-1ubuntu0.7

Ubuntu 16.04 LTS:
  haproxy                         1.6.3-1ubuntu0.3

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

References:
  https://usn.ubuntu.com/4174-1
  CVE-2019-18277

Package Information:
  https://launchpad.net/ubuntu/+source/haproxy/2.0.5-1ubuntu0.2
  https://launchpad.net/ubuntu/+source/haproxy/1.8.19-1ubuntu1.2
  https://launchpad.net/ubuntu/+source/haproxy/1.8.8-1ubuntu0.7
  https://launchpad.net/ubuntu/+source/haproxy/1.6.3-1ubuntu0.3