A Zstandard security update has been released for Ubuntu Linux 16.04 ESM.

USN-5593-1: Zstandard vulnerability

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Ubuntu Security Notice USN-5593-1
September 01, 2022

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

- Ubuntu 16.04 ESM

Summary:

Zstandard could be made to execute arbitrary code if it received specially
crafted input.

Software Description:
- libzstd: fast lossless compression algorithm

Details:

It was discovered that Zstandard incorrectly handled certain inputs.
An attacker could possibly use this issue to execute arbitrary code.

Update instructions:

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

Ubuntu 16.04 ESM:
libzstd1 1.3.1+dfsg-1~ubuntu0.16.04.1+esm2
zstd 1.3.1+dfsg-1~ubuntu0.16.04.1+esm2

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

References:
  https://ubuntu.com/security/notices/USN-5593-1
CVE-2019-11922