Several security issues were fixed in the Apache HTTP server.
It was discovered that the Apache HTTP Server incorrectly parsed chunk headers. A remote attacker could possibly use this issue to perform HTTP request smuggling attacks. (CVE-2015-3183)
27 July 2015
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in the Apache HTTP server.
It was discovered that the Apache HTTP Server incorrectly parsed chunk headers. A remote attacker could possibly use this issue to perform HTTP request smuggling attacks. (CVE-2015-3183)
It was discovered that the Apache HTTP Server incorrectly handled the ap_some_auth_required API. A remote attacker could possibly use this issue to bypass intended access restrictions. This issue only affected Ubuntu 14.04 LTS and Ubuntu 15.04. (CVE-2015-3185)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system update will make all the necessary changes.