Jenkins Secret Injection: A 3-Part Demo with Real-World Pitfalls
In this demo series, I walk through how secrets are handled in Jenkins the good, the bad, and the risky. Watch and learn how a masked secret can still leak silently if not used carefully.
Creating Jenkins Credentials
In the first video, we walk through the creation of a secret credential in Jenkins:
✅ What we did:
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Navigated to Manage Jenkins > Credentials
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Added a new Secret Text credential
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Gave it a recognizable ID (e.g.,
secret-demo)
🔐 Why it matters:
This is the first and most important step to make secrets securely available to Jenkins pipelines without hardcoding them.
Injecting and Echoing Secrets in Pipelines
In the second video, we created a Jenkins Pipeline Job named secret-injection and injected the secret using the withCredentials block.
Jenkins warned us:
A secret was passed to "echo" using Groovy String interpolation, which is insecure.
🛡️ Jenkins masks the secret in logs (****) and alerts developers not to use Groovy string interpolation for secrets.
Writing Secrets to Files (and Why That's Risky)
This video demonstrates the real vulnerability: redirecting secrets to files.
🧨 What we found:
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The secret was not visible in Jenkins logs (masked as
****) -
But the file leaked
.txtstored the raw secret in plaintext
📛 This could lead to:
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Secret exposure through archived artifacts
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Unintentional sharing between jobs or users
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Violations of compliance/security policies
Final Thoughts
Jenkins has strong features for secret masking, but it's only as secure as how you use it. This demo series helps you visualize:
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What Jenkins protects you from
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What you need to protect yourself from
If you found this helpful, don’t forget to share it with your team and fellow DevOps engineers. Stay secure! 🔐💡
