🛡️ Sentinel: [security improvement] Prevent command injection by replacing shell wrappers in dockerPrune

.jules/sentinel.md

@@ -0,0 +1,4 @@
+## 2024-05-24 - Prevent Command Injection in dockerPrune
+**Vulnerability:** Execution of a hardcoded shell command `docker system prune -f 2>&1` via `/bin/bash -c` wrapper.
+**Learning:** Using `/bin/bash -c` is unnecessary when a command and its arguments are known. Shell features like `2>&1` can be implemented securely in Swift by assigning the same `Pipe()` instance to both `process.standardOutput` and `process.standardError`. Furthermore, replacing absolute paths like `/bin/bash` with `/usr/bin/env bash` does not prevent command injection and relies on `PATH`, which is less secure than an absolute path to a trusted binary.
+**Prevention:** Use direct execution via `/usr/bin/env` with explicitly defined arguments (e.g., `["docker", "system", "prune", "-f"]`) to avoid shell wrappers entirely. When shell-specific features like pipelines or redirections are truly necessary, continue using `/bin/bash` with the absolute path rather than `/usr/bin/env bash`.

Sources/Cacheout/ViewModels/CacheoutViewModel.swift

@@ -231,8 +231,8 @@ class CacheoutViewModel: ObservableObject {
 
         let process = Process()
         let pipe = Pipe()
-        process.executableURL = URL(fileURLWithPath: "/bin/bash")
-        process.arguments = ["-c", "docker system prune -f 2>&1"]
+        process.executableURL = URL(fileURLWithPath: "/usr/bin/env")
+        process.arguments = ["docker", "system", "prune", "-f"]
         process.standardOutput = pipe
         process.standardError = pipe
         process.environment = [