A step-by-step checklist to secure Ubuntu Linux:

Download Latest CIS Benchmark

Free to Everyone

For Ubuntu Linux 20.04 (CIS Ubuntu Linux 20.04 LTS Benchmark version 1.1.0)

CIS has worked with the community since 2013 to publish a benchmark for Ubuntu Linux

Join the Ubuntu Linux community

Other CIS Benchmark versions:

For Ubuntu Linux (CIS Ubuntu Linux 14.04 LTS Benchmark version 2.1.0)

Complete CIS Benchmark Archive

Use a CIS Hardened Image

Buy Per Server Hour

CIS Hardened Image available for Benchmark version 1.0.0

Assess and/or remediate

Only Available to CIS SecureSuite Members

Build Kit available for Benchmark version 1.0.0

CIS-CAT Pro is included with membership and can automatically test for compliance and remediate with this benchmark.

Ubuntu Linux is in CIS-CAT Lite edition too
Try CIS-CAT Lite for free