By: Karrie Westmoreland
In my years of penetration testing and security consulting, I have learned two truths. First, vulnerabilities wait for no one. Second, if patching is not automated, it will be delayed, and those delays can eventually come back to bite you. I have lost count of the times a client said, “We will handle that next sprint,” only to find their systems in the headlines a few weeks later.
When patching lives inside your CI/CD pipeline, it stops being a “special event” and becomes a natural, repeatable process. No one has to run around at 2 a.m. manually pushing fixes. Threat actors thrive on lag and inconsistency. A pipeline that patches in stride starves them of that advantage.
The process is simple in theory, but it must be designed with discipline.
It begins with detection. Vulnerabilities can come from your own code, container base images, operating systems, or even that “tiny” library someone added to solve a date-formatting problem three years ago. Detection is only half the battle, though.
Next is prioritization. Not every vulnerability deserves a total production freeze. Look at severity scores, yes, but also check if the flaw is being actively exploited, whether it is internet-facing, and whether compensating controls already exist. The Known Exploited Vulnerabilities (KEV) list and Exploit Prediction Scoring System (EPSS) can help you separate issues that need fixing today from those that can be bundled into the weekly update.
Once the decision is made, you move to patch creation. This could be an updated dependency, a rebuilt container image, or an operating system update. Your pipeline must treat the patch like any other feature: build it, test it, and verify it before it moves forward. Finally, stage and deploy it progressively while monitoring closely. If something goes wrong, the rollback should be automatic, not a 15-minute Slack debate.
Dependencies are like uninvited houseguests. Sometimes they help, sometimes they cause trouble, and sometimes they forget to leave. I once found a finance company running a six-year-old library with a known remote code execution flaw simply because “it still worked.” It worked for them, and unfortunately, it also worked for the criminal group that breached them.
This is why automated dependency update tools are essential. They act as house managers, keeping things fresh and replacing dangerous parts before they become liabilities. The pipeline should cover everything: application libraries, base images, and even build tools themselves. Neglecting one layer is like locking your front door while leaving the back gate swinging in the wind.
Every build should produce a software bill of materials (SBOM). Think of it as your ingredient list. Without it, you have no idea what you are actually serving to production. Once you know what is in the build, scan it for vulnerabilities. Do not let artifacts move forward if they contain unpatched high or critical issues.
Signing builds and recording provenance means you can prove they came from your pipeline and not a compromised source. Minimal base images are also a gift to your future self. Fewer packages mean fewer vulnerabilities to patch later. As one of my mentors used to say, “The best patch is the one you do not have to install.”
A patch that fixes a security hole but breaks your checkout process is not a win. This is why you must have real testing in place before promoting a patch.
At a logistics company I worked with, we deployed patches to a staging environment that mirrored production almost exactly. We rolled them out to one warehouse at a time, watching key metrics. If performance or reliability dipped, the system rolled back instantly. The ops lead told me it was the first time in years he could go home on a patch day without worrying. That is the power of combining security with release discipline.
Applications often get the spotlight, but the systems they run on can quietly collect vulnerabilities for years. I once saw Kubernetes nodes running an OS so outdated it might as well have been wearing vintage flares. The applications on top were up to date, but the foundation was riddled with weaknesses.
Automated node rotation and scheduled rebuilds keep infrastructure fresh. If you use containers, rebuild them regularly from updated base images, even if no code has changed. Live patching can cover urgent cases where restarts are not possible, but it is not a replacement for proper maintenance.
Automation handles consistency, but people set the rules. Define service level objectives for patching. For example, critical vulnerabilities that are actively exploited should be addressed within seventy-two hours. Medium risk issues can be batched into a weekly update.
When delays are unavoidable, exceptions should be documented and set to expire automatically. I have seen exceptions from “temporary” decisions turn into multi-year liabilities. An expiring exception forces the issue back onto the radar before it becomes part of the scenery.
A patch rollout without observability is like flying a plane without instruments. You might be fine, or you might be flying straight toward a mountain. Monitoring should track both application performance and security posture during and after deployment. Look for deviations from baseline. Alert if they appear. Track metrics like mean time to remediate vulnerabilities and percentage of workloads on patched builds. These numbers reveal whether your patching process is improving or merely existing.
I have heard every excuse for skipping patches. “We cannot reboot the database” is solved with failovers or managed services. “Legacy apps will break” means you need a project plan for upgrades, not indefinite avoidance. “False positives keep blocking us” can be managed with temporary suppressions that expire and require documented justification.
None of these problems are insurmountable. They just need planning, the right tooling, and a refusal to let patching be optional.
The best example I have seen of pipeline-based patching in action was the day a high-impact OpenSSL vulnerability dropped. At one client, dependency bots had updates queued within hours. Builds completed with the new version, tests passed, and canary deployments were out before the end of the business day. By the time the news cycle hit peak panic, they were already protected.
That is the goal: when the next zero-day appears, your response is measured, predictable, and quiet. No late nights. No frantic war rooms. Just another successful run through the pipeline.
Patching inside your CI/CD pipeline is not just a technical win. It is a cultural shift. It takes security from being an occasional firefight to an everyday habit. Threat actors do not take days off, so neither should your defenses. The beauty of automation is that you do not have to stay up at night to keep pace.
When patching is built into the pipeline, it stops being a mad scramble and starts feeling like muscle memory. That is when you know you have moved from trying to be secure to actually being secure.
I have seen the difference firsthand. The teams who master this sleep better, ship faster, and spend their incident response time on practice drills instead of real disasters. The only ones who miss the old way are the folks who enjoyed free pizza during all-night war rooms.
How does your team handle patching today? Is it automated and uneventful, or still a heroic event when something critical drops? Share your best or worst patching war story in the comments. Extra credit if it involves too much caffeine, questionable takeout, and at least one unexpected plot twist.
We are diving into the Shift Left approach in security. What it means, how to do it right, and why starting earlier in the development process can save you from late-stage chaos.