trivy/docs/mkdocs/installation/debian_ubuntu.md

Add repository to /etc/apt/sources.list.d.

$ sudo apt-get install wget apt-transport-https gnupg lsb-release
$ wget -qO - https://aquasecurity.github.io/trivy-repo/deb/public.key | sudo apt-key add -
$ echo deb https://aquasecurity.github.io/trivy-repo/deb $(lsb_release -sc) main | sudo tee -a /etc/apt/sources.list.d/trivy.list
$ sudo apt-get update
$ sudo apt-get install trivy

or

$ wget https://github.com/aquasecurity/trivy/releases/download/{TRIVY_VERSION}/trivy_{TRIVY_VERSION}_Linux-64bit.deb
$ sudo dpkg -i trivy_{TRIVY_VERSION}_Linux-64bit.deb