Exim could be made to crash or run programs if it received specially crafted network traffic.
It was discovered that Exim incorrectly handled memory in the ESMTP CHUNKING extension. A remote attacker could use this issue to cause Exim to crash, resulting in a denial of service, or possibly execute arbitrary code. The default compiler options for affected releases should reduce the vulnerability to a denial of service.
27 November 2017
A security issue affects these releases of Ubuntu and its derivatives:
Exim could be made to crash or run programs if it received specially crafted network traffic.
It was discovered that Exim incorrectly handled memory in the ESMTP CHUNKING extension. A remote attacker could use this issue to cause Exim to crash, resulting in a denial of service, or possibly execute arbitrary code. The default compiler options for affected releases should reduce the vulnerability to a denial of service.
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.