CVE-2021-31821
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedWhen the Windows Tentacle docker image starts up it logs all the commands that it runs along with the arguments, which writes the Octopus Server API key in plaintext. This does not affect the Linux Docker image
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceThe Windows Tentacle Docker image has a logging vulnerability where startup commands and their arguments are written to logs in plaintext, exposing the Octopus Server API key. This occurs because the Docker entrypoint script logs all executed commands including sensitive arguments.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data< 6.1.1266CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify if running Octopus Tentacle Docker imageCheck the Docker image name: run 'docker images' or inspect the container metadata. Look for images containing 'tentacle' from the 'octopusdeploy' registry.Affected if The container is running an Octopus Tentacle Docker image from octopusdeploy registry on Windows hosts.
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Check installed Tentacle versionRun 'docker exec <container_id> --version' or inspect the image metadata via 'docker inspect <image_id>' to find the Tentacle version string.Affected if The Tentacle version is below 6.1.1266 (e.g., 6.1.1000, 6.0.500, etc.).
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Inspect the entrypoint script for logging of argumentsExamine the Docker entrypoint script inside the container: 'docker exec <container_id> cat /Tentacle/Start-Tentacle.ps1' or equivalent entrypoint path. Look for command-line logging statements that echo or write $args or $CommandLine to log files.Affected if The entrypoint script contains statements that log full command-line arguments (including -apiKey or --server) to stdout/stderr or log files.
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Examine container logs for plaintext sensitive dataRun 'docker logs <container_id>' and search for API key patterns: look for strings containing 'Octopus Server' URL with 'api-' tokens, or '-apiKey' followed by alphanumeric strings.Affected if The Docker logs contain plaintext API keys (strings starting with 'API-') or other sensitive arguments passed at startup.
A user is affected if they are running a Windows Octopus Tentacle Docker image version below 6.1.1266 and their container logs expose plaintext API keys or other sensitive startup arguments.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped6.1.1266
Upgrade to a patched Tentacle Docker image version that masks sensitive arguments in logs, or modify the entrypoint script to exclude sensitive parameters from logging.
Upgrade to Tentacle Docker image version 6.1.1266 or later
- Pull the updated Windows Tentacle Docker image with version 6.1.1266 or later: docker pull octopusdeploy/tentacle:6.1.1266
- Update your Docker deployment configuration to use the new image version
- Redeploy the container with the updated image
- Verify the container starts successfully and check logs to confirm API keys are no longer being logged in plaintext
- If using Kubernetes or orchestrators, update the image tag in your deployment manifests
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA2.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2021-31821 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-31821 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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