fix: sanitize shell input

- Replaced unsafe string concatenation with `shlex.join()` for POSIX systems, `mslex.join()` for Windows systems.
- Add utility function `safe_join`.
- Modified `pyproject.toml` to include `mslex` dependency for Windows environments.

libs/python/computer/computer/providers/lume_api.py

@@ -10,6 +10,8 @@ import subprocess
 import urllib.parse
 from typing import Any, Dict, List, Optional
 
+from computer.utils import safe_join
+
 # Setup logging
 logger = logging.getLogger(__name__)
 
@@ -59,7 +61,7 @@ def lume_api_get(
     # --max-time: Maximum time for the whole operation (20 seconds)
     # -f: Fail silently (no output at all) on server errors
     # Add single quotes around URL to ensure special characters are handled correctly
-    cmd = ["curl", "--connect-timeout", "15", "--max-time", "20", "-s", "-f", f"'{api_url}'"]
+    cmd = ["curl", "--connect-timeout", "15", "--max-time", "20", "-s", "-f", api_url]
 
     # For logging and display, show the properly escaped URL
     display_cmd = ["curl", "--connect-timeout", "15", "--max-time", "20", "-s", "-f", api_url]
@@ -71,7 +73,7 @@ def lume_api_get(
     # Execute the command - for execution we need to use shell=True to handle URLs with special characters
     try:
         # Use a single string with shell=True for proper URL handling
-        shell_cmd = " ".join(cmd)
+        shell_cmd = safe_join(cmd)
         result = subprocess.run(shell_cmd, shell=True, capture_output=True, text=True)
 
         # Handle curl exit codes
@@ -514,7 +516,7 @@ def lume_api_delete(
         "-s",
         "-X",
         "DELETE",
-        f"'{api_url}'",
+        api_url,
     ]
 
     # For logging and display, show the properly escaped URL
@@ -537,7 +539,7 @@ def lume_api_delete(
     # Execute the command - for execution we need to use shell=True to handle URLs with special characters
     try:
         # Use a single string with shell=True for proper URL handling
-        shell_cmd = " ".join(cmd)
+        shell_cmd = safe_join(cmd)
         result = subprocess.run(shell_cmd, shell=True, capture_output=True, text=True)
 
         # Handle curl exit codes

libs/python/computer/computer/utils.py

@@ -1,7 +1,10 @@
 import base64
 import io
+import os
+import shlex
 from typing import Any, Dict, Optional, Tuple
 
+import mslex
 from PIL import Image, ImageDraw
 
 
@@ -104,3 +107,25 @@ def parse_vm_info(vm_info: Dict[str, Any]) -> Optional[Dict[str, Any]]:
     """Parse VM info from pylume response."""
     if not vm_info:
         return None
+
+
+def safe_join(argv: list[str]) -> str:
+    """
+    Return a platform-correct string that safely quotes `argv` for shell execution.
+
+    - On POSIX: uses `shlex.join`.
+    - On Windows: uses `shlex.join`.
+
+    Args:
+        argv: iterable of argument strings (will be coerced to str).
+
+    Returns:
+        A safely quoted command-line string appropriate for the current platform that protects against
+        shell injection vulnerabilities.
+    """
+    if os.name == "nt":
+        # On Windows, use mslex for proper quoting
+        return mslex.join(argv)
+    else:
+        # On POSIX systems, use shlex
+        return shlex.join(argv)

libs/python/computer/pyproject.toml

@@ -16,7 +16,8 @@ dependencies = [
     "websockets>=12.0",
     "aiohttp>=3.9.0",
     "cua-core>=0.1.0,<0.2.0",
-    "pydantic>=2.11.1"
+    "pydantic>=2.11.1",
+    "mslex>=1.3.0",
 ]
 requires-python = ">=3.12"
 
@@ -47,4 +48,4 @@ source-includes = ["tests/", "README.md", "LICENSE"]
 [tool.pytest.ini_options]
 asyncio_mode = "auto"
 testpaths = ["tests"]
-python_files = "test_*.py"
+python_files = "test_*.py"