A GNU C Library security update has been released for Ubuntu Linux 16.04 ESM.

USN-5768-1: GNU C Library vulnerabilities

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Ubuntu Security Notice USN-5768-1
December 08, 2022

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

- Ubuntu 16.04 ESM

Summary:

Several security issues were fixed in GNU C Library.

Software Description:
- glibc: GNU C Library

Details:

Jan Engelhardt, Tavis Ormandy, and others discovered that the GNU C Library
iconv feature incorrectly handled certain input sequences. An attacker
could possibly use this issue to cause the GNU C Library to hang or crash,
resulting in a denial of service. (CVE-2016-10228, CVE-2019-25013,
CVE-2020-27618)

It was discovered that the GNU C Library did not properly handled DNS
responses when ENDS0 is enabled. An attacker could possibly use this issue
to cause fragmentation-based attacks. (CVE-2017-12132)

Update instructions:

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

Ubuntu 16.04 ESM:
libc6 2.23-0ubuntu11.3+esm3

After a standard system update you need to reboot your computer to make
all the necessary changes.

References:
  https://ubuntu.com/security/notices/USN-5768-1
CVE-2016-10228, CVE-2017-12132, CVE-2019-25013, CVE-2020-27618