Docker CLI leaks private registry credentials to registry-1.docker.io

Impact

A bug was found in the Docker CLI where running docker login my-private-registry.example.com with a misconfigured configuration file (typically ~/.docker/config.json) listing a credsStore or credHelpers that could not be executed would result in any provided credentials being sent to registry-1.docker.io rather than the intended private registry.

Patches

This bug has been fixed in Docker CLI 20.10.9. Users should update to this version as soon as possible.

Workarounds

Ensure that any configured credsStore or credHelpers entries in the configuration file reference an installed credential helper that is executable and on the PATH.

For more information

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• Email us at [email protected] if you think you’ve found a security bug