Summary
The transformation policy template feature in Kgateway versions through 2.0.4 allows users with TrafficPolicy creation permissions to craft transformations that read and expose arbitrary files from the dataplane container filesystem.
Description
Impact
Users with permissions to create a TrafficPolicy can create a transformation that returns files from within the dataplane container. While no secrets are mounted to the container by default, users who mount custom volumes to the dataplane should be aware of potential data exposure through this vulnerability.
This could allow unauthorized access to:
- Configuration files within the container
- Custom mounted volumes and their contents
- Any files accessible to the dataplane container process
Note: Updated availability score to high, as under some configurations this can prevent xDS updates.
Patches
Upgrade to version 2.0.5 or 2.1.0. These versions include an updated transformation filter in envoy-gloo that prevents file access through transformation templates.
Workarounds
If you are not using transformations, you can disallow TrafficPolicy creation or restrict transformation usage using a ValidatingAdmissionPolicy to prevent exploitation while preparing to upgrade.
References
Credits
Kindly reported by @rikatz
For More Information
If you have any questions or comments about this advisory, please reach out in slack https://cloud-native.slack.com/archives/C080D3PJMS4
rikatz Reporter
Summary
The transformation policy template feature in Kgateway versions through 2.0.4 allows users with TrafficPolicy creation permissions to craft transformations that read and expose arbitrary files from the dataplane container filesystem.
Description
Impact
Users with permissions to create a TrafficPolicy can create a transformation that returns files from within the dataplane container. While no secrets are mounted to the container by default, users who mount custom volumes to the dataplane should be aware of potential data exposure through this vulnerability.
This could allow unauthorized access to:
Note: Updated availability score to high, as under some configurations this can prevent xDS updates.
Patches
Upgrade to version 2.0.5 or 2.1.0. These versions include an updated transformation filter in envoy-gloo that prevents file access through transformation templates.
Workarounds
If you are not using transformations, you can disallow TrafficPolicy creation or restrict transformation usage using a ValidatingAdmissionPolicy to prevent exploitation while preparing to upgrade.
References
Credits
Kindly reported by @rikatz
For More Information
If you have any questions or comments about this advisory, please reach out in slack https://cloud-native.slack.com/archives/C080D3PJMS4