A file security update has been released for both Ubuntu 14.04 ESM and Ubuntu 12.04 ESM. Ubuntu Extended Security Maintenance (ESM) is a paid security subscription provided by Canonical Ltd.

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Ubuntu Security Notice USN-4172-2

October 31, 2019

file vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 14.04 ESM
- Ubuntu 12.04 ESM

Summary:

file could be made to crash or run programs if it opened a specially crafted file.

Software Description:
- file: Tool to determine file types

Details:

USN-4172-1 fixed a vulnerability in file. This update provides the corresponding update for Ubuntu 12.04 ESM Ubuntu 14.04 ESM.
Original advisory details:

It was discovered that file incorrectly handled certain malformed files. Anattacker could use this issue to cause 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 14.04 ESM:
file 1:5.14-2ubuntu3.4+esm1
libmagic1 1:5.14-2ubuntu3.4+esm1

Ubuntu 12.04 ESM:
file 5.09-2ubuntu0.8
libmagic1 5.09-2ubuntu0.8

In general, a standard system update will make all the necessary changes.
References:
https://usn.ubuntu.com/4172-2
https://usn.ubuntu.com/4172-1
CVE-2019-18218