Image analysis sandbox
The image analysis sandbox lets you dynamically analyze the runtime behaviour of images before running them in your development and production environments.
The analysis mechanism collects and displays container behaviours by safely exercising the image in a sandbox machine. It also exposes risks and identifies suspicious dependencies buried deep in your software supply chain that would otherwise be missed by static analysis for vulnerabilities and compliance issues.
Running the analysis is supported for Linux images on Docker container runtime.
Setup the sandbox machine
In order to run a sandbox analysis for an image, you first need to set up a dedicated sandbox virtual machine.
- The sandbox machine should have connectivity to Prisma Cloud Compute Console.
- The machine must be a Linux VM.
- Docker should be installed on the machine.
When setting up the VM, follow the guidelines below to make sure potential malware doesn’t exploit your sandbox:
- Make sure that the kernel is up to date.
- Make sure that Docker and Runc are up to date.
- Make sure all the software components on the machine are up to date (to make sure there is no other vulnerable component on the machine).
- The VM should be as isolated as possible. Run the VM in a dedicated network, separate from production. If other services run alongside the sandbox VM in the same local network, set up firewall rules to ensure the sandbox VM cannot reach them.
- If the VM runs in the cloud, it shouldn’t run with any service account.
It is recommended to avoid running a Defender on the same machine used as the sandbox VM. Running a Defender on this machine might cause the image that is being analyzed in the sandbox to also be presented under
Monitor > Vulnerabilities/Compliance > Images > Deployed imagesas an image running in the environment.
Setup the sandbox user
Create a dedicated, least-privileged user for running the image analysis sandbox.
Running the sandbox with a privileged role (Admin, Operator) is a risk in case a malware escapes (by using a zero day, one day, exploit misconfiguration, etc.), and can potentially use this role to take over Prisma.
- Create a custom role underManage > Authentication > Roleswith Write permissions for Container Runtime Results and Read permissions for CI Results. For roles created via the API, also add Write permission for User.
- Create a sandbox user and assign it with the new custom role you created.
- When triggering the sandbox analysis via twistcli, use the sandbox user credentials. It is recommended to use a short-lived token (available underManage > System > Utilities) rather then a username and password.
Running the sandbox command
Triggering a sandbox analysis is done by executing the twistcli sandbox command on an image. After the command is triggered, Prisma Cloud’s sandbox mechanism runs the container, and starts tracing its behaviour. The events occuring on the running container are collected, and are later being analyzed to discover suspicious behaviours.
The usage of the twistcli sandbox command is very similar to running a container image using docker:
$ twistcli sandbox [OPTIONS] IMAGE [COMMAND] [ARG...]
$ twistcli sandbox --address https://<console-address>:8083 --token 'your-api-token' --analysis-duration 2m -v "$PWD":/app python:3 python3 /app/server.py
The entrypoint and arguments should be specified after the image. If an entrypoint isn’t specified, the default entrypoint of the image will be used.
- Complete URL for Console, including the protocol and port. Only the HTTPS protocol is supported. By default, Console listens to HTTPS on port 8083, although your administrator can configure Console to listen on a different port. Defaults to https://127.0.0.1:8083.Example: --address https://console.example.com:8083
- The duration of the analysis in a Go duration string format. The default duration is 1 minute.Adjust the duration according to your image. A longer duration may allow detecting more behaviours. An analysis duration that is too short might cause missing some of the suspicious findings that could have been detected on the container.Example: --analysis-duration 2m30sThe analysis duration can be shorter than the duration you specified, if the container exits before the analysis time ends.When WildFire integration is enabled, the analysis duration can be longer than specified, since the communication with WildFire may take longer than the analysis duration. When the specified duration is met, Prisma Cloud stops the container, so no more events are collected, but is waiting for WildFire verdict to publish the results.
- A src:dst pair to mount a volume to the running container. Repeat flag for each mount.Any volume that is shared with the sandbox will be accessible to a potential malware exists on the container. Therefore, carefully consider the usage of volumes.
The exit code is 0 if the sandbox analysis verdict is "Passed". If the verdict is "Failed", the exit code is 1.
The criteria for passing or failing the sandbox analysis is determined by the severity of the suspicious findings detected during the analysis. The analysis verdict is "Failed" when there is at least one finding with Critical or High severity. Otherwise, the verdict is "Passed".
Another reason why twistcli sandbox might return an exit code of 1 is if the analysis failed due to an error.
Sandbox analysis results
- Exits with a return value.
- Outputs a summary of the results, including a verdict.
- Outputs a link to the results report in the Console UI.
The results report in the Console UI includes the analysis summary and verdict, a list of suspicious detections found on the image, and the entire container behaviour events occurred during container runtime.