Code: :~# apt-cache rdepends --installed passenger passenger Reverse Depends: libapache2-mod-passenger Apache logs, Code: age/Cor/SecurityUpdateChecker.h:521 ]: A security update is available for your version (6.0.10) of Phusion Passenger(R). We strongly recommend upgrading to version 6.0.17. From search results here i figure it is safe to, Code: a2dismod passenger since i have no client with the need for ruby code, could use a confirmation though.