🛡️ Sentinel: [CRITICAL] Fix arbitrary code execution vulnerability in AST type validation

.jules/sentinel.md

@@ -4,3 +4,8 @@
 **Vulnerability:** Found an unused `_attempt_import` function in `src/codeweaver/server/mcp/server.py` that dynamically imports a module directly from unvalidated configuration (`import_module(mw.rsplit(".", 1)[0])`), leading to potential arbitrary code execution.
 **Learning:** Functions that perform dynamic imports should not be left around in the codebase if they are unused, especially if they are designed to take unvalidated strings as input.
 **Prevention:** Avoid dynamic imports based on configuration or inputs without strict whitelisting. Use tools like `semgrep` with python security rules to actively catch these patterns.
+
+## 2026-06-09 - Arbitrary Code Execution via unrestricted ast.Call in eval()
+**Vulnerability:** Found a vulnerability in `src/codeweaver/core/di/container.py` where `eval()` was used to evaluate dynamic type strings. While an AST validator checked for safe nodes, it allowed unrestricted `ast.Call` nodes, meaning any function available in the global namespace or builtins could be executed during dependency injection resolution.
+**Learning:** Even when using a restricted `eval()` environment with a filtered globals dict and AST validation, permitting generic `ast.Call` execution still allows for severe security holes (Arbitrary Code Execution) if an attacker can manipulate the input strings (type hints).
+**Prevention:** Strictly whitelist allowed functions in AST validation (like `Depends`, `Field`, etc.) when evaluating type annotations, and never allow generic `ast.Call` nodes.

src/codeweaver/core/di/container.py

@@ -84,7 +84,7 @@ def __init__(self) -> None:
         self._request_cache: dict[Any, Any] = {}  # Keys can be types or callables
         self._providers_loaded: bool = False  # Track if auto-discovery has run
 
-    def _safe_eval_type(self, type_str: str, globalns: dict[str, Any]) -> Any | None:
+    def _safe_eval_type(self, type_str: str, globalns: dict[str, Any]) -> Any | None:  # noqa: C901
         """Safely evaluate a type string using AST validation.
 
         Parses the type string into an AST, validates that it contains only safe
@@ -136,6 +136,26 @@ def generic_visit(self, node: ast.AST) -> None:
                 if isinstance(node, ast.Attribute) and node.attr.startswith("__"):
                     raise TypeError(f"Forbidden dunder attribute: {node.attr}")
 
+                # Security: Restrict ast.Call to a strict whitelist of known safe functions to
+                # prevent Arbitrary Code Execution (ACE) during the dynamic type evaluation in `eval()`.
+                if isinstance(node, ast.Call):
+                    allowed_calls = {
+                        "Depends",
+                        "depends",
+                        "Field",
+                        "PrivateAttr",
+                        "Tag",
+                        "Parameter",
+                    }
+                    func_name = None
+                    if isinstance(node.func, ast.Name):
+                        func_name = node.func.id
+                    elif isinstance(node.func, ast.Attribute):
+                        func_name = node.func.attr
+
+                    if func_name not in allowed_calls:
+                        raise TypeError(f"Forbidden call to function: {func_name}")
+
                 super().generic_visit(node)
 
         try: