Does Discourse container use unattended-upgrades?

After further digging, it appears that unattended-upgrades is installed but not running on the Discourse docker container.

First, it’s clearly installed

root@osestaging1-discourse-ose:/var/www/discourse# dpkg -l | grep -i unatt
ii  unattended-upgrades             1.11.2                       all          automatic installation of security upgrades
root@osestaging1-discourse-ose:/var/www/discourse# 

Further inspecting of the unattended-upgrades package’s config per the relevant Debian wiki article shows

The default config looks sane

root@osestaging1-discourse-ose:/var/www/discourse# grep -ir 'origin=' /etc/apt/apt.conf.d/50unattended-upgrades 
//      "origin=Debian,codename=${distro_codename}-updates";
//      "origin=Debian,codename=${distro_codename}-proposed-updates";
		"origin=Debian,codename=${distro_codename},label=Debian";
		"origin=Debian,codename=${distro_codename},label=Debian-Security";
root@osestaging1-discourse-ose:/var/www/discourse# cat /etc/apt/apt.conf.d/20auto-upgrades 
APT::Periodic::Update-Package-Lists "1";
APT::Periodic::Unattended-Upgrade "1";
root@osestaging1-discourse-ose:/var/www/discourse# 

But checking the logs show the last entry was 1 month ago

root@osestaging1-discourse-ose:/var/www/discourse# tail -f /var/log/unattended-upgrades/unattended-upgrades*.log
==> /var/log/unattended-upgrades/unattended-upgrades-dpkg.log <==
Log started: 2019-11-17  12:34:54
(Reading database ... 44559 files and directories currently installed.)
Removing freetype2-doc (2.9.1-3+deb10u1) ...
Log ended: 2019-11-17  12:34:54

Log started: 2019-11-17  12:34:56
(Reading database ... 44389 files and directories currently installed.)
Removing libjs-jquery (3.3.1~dfsg-3) ...
Log ended: 2019-11-17  12:34:57


==> /var/log/unattended-upgrades/unattended-upgrades.log <==
2019-11-26 16:37:47,549 INFO Initial blacklist : 
2019-11-26 16:37:47,550 INFO Initial whitelist: 
2019-11-26 16:37:47,551 INFO Starting unattended upgrades script
2019-11-26 16:37:47,552 INFO Allowed origins are: origin=Debian,codename=buster,label=Debian, origin=Debian,codename=buster,label=Debian-Security
2019-11-26 16:37:50,811 INFO Checking if system is running on battery is skipped. Please install powermgmt-base package to check power status and skip installing updates when the system is running on battery.
2019-11-26 16:37:50,814 INFO Initial blacklist : 
2019-11-26 16:37:50,815 INFO Initial whitelist: 
2019-11-26 16:37:50,815 INFO Starting unattended upgrades script
2019-11-26 16:37:50,815 INFO Allowed origins are: origin=Debian,codename=buster,label=Debian, origin=Debian,codename=buster,label=Debian-Security
2019-11-26 16:37:53,119 INFO No packages found that can be upgraded unattended and no pending auto-removals
^C
root@osestaging1-discourse-ose:/var/www/discourse# 

…Even though the default systemd timers defined for unattended-upgrades are set to run at least once per day

root@osestaging1-discourse-ose:/var/www/discourse# cat /lib/systemd/system/apt-daily.timer
[Unit]
Description=Daily apt download activities

[Timer]
OnCalendar=*-*-* 6,18:00
RandomizedDelaySec=12h
Persistent=true

[Install]
WantedBy=timers.target
root@osestaging1-discourse-ose:/var/www/discourse# cat /etc/systemd/system/apt-daily.timer.d/override.conf
cat: /etc/systemd/system/apt-daily.timer.d/override.conf: No such file or directory
root@osestaging1-discourse-ose:/var/www/discourse# cat /lib/systemd/system/apt-daily-upgrade.timer
[Unit]
Description=Daily apt upgrade and clean activities
After=apt-daily.timer

[Timer]
OnCalendar=*-*-* 6:00
RandomizedDelaySec=60m
Persistent=true

[Install]
WantedBy=timers.target
root@osestaging1-discourse-ose:/var/www/discourse# cat /etc/systemd/system/apt-daily-upgrade.timer.d/override.conf
cat: /etc/systemd/system/apt-daily-upgrade.timer.d/override.conf: No such file or directory
root@osestaging1-discourse-ose:/var/www/discourse# 

But, indeed, those timers are disabled.

root@osestaging1-discourse-ose:/var/www/discourse# sudo systemctl status apt-daily.timer
System has not been booted with systemd as init system (PID 1). Can't operate.
Failed to connect to bus: Host is down
root@osestaging1-discourse-ose:/var/www/discourse# sudo systemctl status apt-daily-upgrade.timer
System has not been booted with systemd as init system (PID 1). Can't operate.
Failed to connect to bus: Host is down
root@osestaging1-discourse-ose:/var/www/discourse# 

This is further confirmed by manually running unattended-upgrades, which just happened to require an update to two git-related packages

root@osestaging1-discourse-ose:/var/www/discourse# sudo unattended-upgrade -d
...
Checking: git ([<Origin component:'main' archive:'stable' origin:'Debian' label:'Debian-Security' site:'security.debian.org' isTrusted:True>])
Checking: git-man ([<Origin component:'main' archive:'stable' origin:'Debian' label:'Debian-Security' site:'security.debian.org' isTrusted:True>])
pkgs that look like they should be upgraded: git   
git-man
...
All upgrades installed
InstCount=0 DelCount=0 BrokenCount=0
Extracting content from /var/log/unattended-upgrades/unattended-upgrades-dpkg.log since 2019-12-24 17:32:55
root@osestaging1-discourse-ose:/var/www/discourse# 

The git version that was updated in the above unattended-upgrades run was git (1:2.20.1-2+deb10u1). I ran this test today (2019-12-24), but the security upgrade had been available to Debian Buster (the OS on which the Discourse docker image is built) for two weeks (since 2019-12-10)!

This is actually a pretty serious upgrade that fixes several vulnerabilities, including two vectors for Remote Code Execution. More info is available at the Debian Security Advisory 4581-1

But git is just an example I happened to stumble on. It’s extremely concerning if the Discourse docker container doesn’t (by default) actually apply security-related patches to its OS.

Is this a bug? Or was this an intentional decision by the Discourse team? Or is this just the default in-lieu of a feature request to enable unattended-upgrades on the Discourse docker container?