GeezerVison

Problem

A batch step image controls the output of the mktemp shell probe. The CLI used that output in a Docker mount argument without validation, so invalid output could change the mount configuration. This was reported to us via HackerOne.

Solution

Require the probe output to be one absolute POSIX path with safe characters. Validate the path again before building the mount, and use one helper to validate executor bind mounts. Add regression tests for mount argument injection.

Verification Evidence

• go test ./internal/batches/...
• The regression test confirms that a comma-delimited mount payload is rejected.