diff --git a/src/main/ssh/ssh-system-transport.integration.test.ts b/src/main/ssh/ssh-system-transport.integration.test.ts
index bf2b639207b..f411712410c 100644
--- a/src/main/ssh/ssh-system-transport.integration.test.ts
+++ b/src/main/ssh/ssh-system-transport.integration.test.ts
@@ -8,7 +8,7 @@ vi.mock('electron', () => ({
 
 // This fixture exercises SSH framing; runtime installation has separate integration coverage.
 vi.mock('./ssh-relay-bun-runtime', () => ({
-  ensureRemoteRelayBunRuntime: vi.fn(async () => process.execPath)
+  ensureRemoteRelayBunRuntime: vi.fn(async () => `${process.env.ORCA_SYSTEM_SSH_PATH}-runtime`)
 }))
 
 import { SshConnection } from './ssh-connection'
@@ -180,6 +180,17 @@ describe('system SSH transport integration', () => {
     process.env.HOME = remoteHome
     process.env.ORCA_RELAY_PATH = relayRoot
     process.env.ORCA_SYSTEM_SSH_PATH = writeFakeSsh(tempDir)
+    // Validate the owned-runtime prefix before handing the framing fixture to Node.
+    const runtime = `${process.env.ORCA_SYSTEM_SSH_PATH}-runtime`
+    writeFileSync(
+      runtime,
+      `#!/bin/sh
+[ "$1" = '--no-env-file' ] && [ "$2" = '--config=/dev/null' ] && [ "$3" = '--no-install' ] || exit 64
+shift 3
+exec '${process.execPath.replaceAll("'", "'\"'\"'")}' "$@"
+`
+    )
+    chmodSync(runtime, 0o755)
     process.env.ORCA_SSH_FORCE_SYSTEM_TRANSPORT = '1'
   })