Five changes separate a throwaway image from a liability
A before/after Dockerfile walkthrough showing the concrete hardening changes that matter most in practice.
Speaker notes
- Walk the before/after side by side, and for each change explain the actual mechanism, not just the label: pinning an exact version instead of `latest` means the same Dockerfile can't silently produce a different, possibly-vulnerable image weeks later; a multi-stage build means compilers and build tools needed only to install dependencies never ship in the final image at all, shrinking the attack surface.
- Emphasize the two changes the tutorial itself calls out as mattering most for real-world risk reduction: never run as root, and never bake secrets into image layers. If an attacker exploits the app, running as an unprivileged user dramatically limits what they can do next; a secret in `ENV` becomes permanently embedded in the image's layer history, extractable by anyone who can pull the image.
- Connect this forward: secrets injected at runtime instead of baked in is the shift-left idea from Module 1 applied to container builds specifically, and it's the direct setup for Module 4's full secrets-management discussion.
Deck map
01
Make security everyone's job
02
Six modules, one continuous defense
03
Security stops being a gate at the end
04
Shift-left: catch it while it's still cheap
05
Think like an attacker, on purpose
06
The cloud secures the cloud, you secure what's inside it
07
Turn the policy PDF into an enforced rule
08
Tooling alone doesn't make you DevSecOps
09
SAST, DAST, SCA: three different questions
10
SAST reads your code without ever running it
11
DAST attacks the running app like a real attacker would
12
The vulnerability three packages deep
13
CVSS tells you how bad, not whether it can reach you
14
No single tool covers the whole OWASP Top 10
15
A container image is more than your app
16
One image scan doesn't see your whole cluster
17
Five changes separate a throwaway image from a liability
18
A container is not a lightweight VM
19
What's inside the image isn't how it's run
20
Kubernetes adds a new set of who-can-do-what questions
21
Kubernetes trusts every pod by default
22
Enforce it automatically, then watch for what slips through
23
Two more names worth knowing: Kyverno and kube-bench
24
One leaked secret bypasses every other control
25
Catch it before the commit, know what to do if it leaks anyway
26
Why environment variables aren't a secrets manager
27
Every app instance gets its own credential, and it expires on its own
28
Not every secret needs a Vault server
29
Long-lived keys are a secret you have to store somewhere
30
Something has to be the first credential
31
Why attack a thousand customers when you can attack one build system
32
A misconfigured trigger can hand your secrets to a stranger's fork
33
A mutable version tag is a promise the maintainer can break
34
Scan the infrastructure definition before it's ever provisioned
35
Know exactly what's inside, prove exactly where it came from
36
One diagram, every module, in the order it runs
37
Passing an audit is not the same as being secure
38
Turn the compliance checklist into a real, running scan
39
Five functions, and which framework to start with
40
ISO 27001 asks for a system, PCI-DSS asks for specific controls
41
Compliance is largely DevSecOps, formalized
42
Every tool from this course, in one place
43
Sixty seconds before the interview
44
What you should be able to explain now