==========================================================================
Ubuntu Security Notice USN-6736-1
April 16, 2024

klibc vulnerabilities
==========================================================================

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

- Ubuntu 23.10
- Ubuntu 22.04 LTS
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS (Available with Ubuntu Pro)
- Ubuntu 16.04 LTS (Available with Ubuntu Pro)
- Ubuntu 14.04 LTS (Available with Ubuntu Pro)

Summary:

Several security issues were fixed in klibc.

Software Description:
- klibc: small utilities built with klibc for early boot

Details:

It was discovered that zlib, vendored in klibc, incorrectly handled pointer
arithmetic. An attacker could use this issue to cause klibc to crash or to
possibly execute arbitrary code. (CVE-2016-9840, CVE-2016-9841)

Danilo Ramos discovered that zlib, vendored in klibc, incorrectly handled
memory when performing certain deflating operations. An attacker could use
this issue to cause klibc to crash or to possibly execute arbitrary code.
(CVE-2018-25032)

Evgeny Legerov discovered that zlib, vendored in klibc, incorrectly handled
memory when performing certain inflate operations. An attacker could use
this issue to cause klibc to crash or to possibly execute arbitrary code.
(CVE-2022-37434)

Update instructions:

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

Ubuntu 23.10:
   klibc-utils                    2.0.13-1ubuntu0.1
   libklibc                        2.0.13-1ubuntu0.1

Ubuntu 22.04 LTS:
   klibc-utils                    2.0.10-4ubuntu0.1
   libklibc                        2.0.10-4ubuntu0.1

Ubuntu 20.04 LTS:
   klibc-utils                    2.0.7-1ubuntu5.2
   libklibc                        2.0.7-1ubuntu5.2

Ubuntu 18.04 LTS (Available with Ubuntu Pro):
   klibc-utils                    2.0.4-9ubuntu2.2+esm1
   libklibc                        2.0.4-9ubuntu2.2+esm1

Ubuntu 16.04 LTS (Available with Ubuntu Pro):
   klibc-utils                    2.0.4-8ubuntu1.16.04.4+esm2
   libklibc                        2.0.4-8ubuntu1.16.04.4+esm2

Ubuntu 14.04 LTS (Available with Ubuntu Pro):
   klibc-utils                    2.0.3-0ubuntu1.14.04.3+esm3
   libklibc                        2.0.3-0ubuntu1.14.04.3+esm3

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

References:
   https://ubuntu.com/security/notices/USN-6736-1
   CVE-2016-9840, CVE-2016-9841, CVE-2018-25032, CVE-2022-37434

Package Information:
   https://launchpad.net/ubuntu/+source/klibc/2.0.13-1ubuntu0.1
   https://launchpad.net/ubuntu/+source/klibc/2.0.10-4ubuntu0.1
   https://launchpad.net/ubuntu/+source/klibc/2.0.7-1ubuntu5.2