security: genericize internal-pattern regexes and document pickle trust boundary (#15)

- pattern-check.yml: replace an environment-specific registry hostname
  pattern with a generic, non-attributable '.corp' TLD pattern (broader
  coverage, no infrastructure naming disclosed).
- AutoBayesModel.save/load: document that model.pkl is a pickle artifact
  and must only be loaded from trusted sources (CWE-502 guidance).
- README: add a security note next to the artifacts list.

No behavior change.

Author: opensource-SantanderAI

.github/workflows/pattern-check.yml

@@ -51,8 +51,8 @@ jobs:
             '\.gluon/'
             'gluon-runner'
             'gluon-app\[bot\]'
-            # Internal package registries
-            'nexus\.alm\.europe\.cloudcenter\.corp'
+            # Internal package registries / internal TLD suffixes (generic)
+            '\.corp\b'
             'artifactory\.santander\.'
             # Internal IPv4 ranges (RFC1918)
             '\b10\.[0-9]+\.[0-9]+\.[0-9]+\b'

README.md

@@ -244,6 +244,12 @@ Training writes these files into `run.output_dir`:
 - `network.json`
 - `model.pkl`
 
+> **Security note:** `model.pkl` is a Python
+> [pickle](https://docs.python.org/3/library/pickle.html) file. Loading a
+> pickle can execute arbitrary code, so call `AutoBayesModel.load()` only on
+> model directories you created yourself or obtained from a source you fully
+> trust.
+
 ## Limits
 
 - Each table can have at most one parent relation.

src/auto_bayesian/model.py

@@ -148,6 +148,11 @@ def save(self, output_dir: str | Path) -> None:
 
         Writes ``model.pkl``, ``metrics.json``, ``network.json``, and (when
         available) ``materialized.parquet`` into ``output_dir``.
+
+        .. note::
+           ``model.pkl`` is a :mod:`pickle` file. Treat saved model
+           directories as trusted artifacts and share them only through
+           channels where they cannot be tampered with.
         """
         output_path = Path(output_dir)
         output_path.mkdir(parents=True, exist_ok=True)
@@ -208,7 +213,14 @@ def save(self, output_dir: str | Path) -> None:
 
     @classmethod
     def load(cls, output_dir: str | Path) -> "AutoBayesModel":
-        """Load a model previously written by :meth:`save`."""
+        """Load a model previously written by :meth:`save`.
+
+        .. warning::
+           ``model.pkl`` is deserialized with :mod:`pickle`, which can
+           execute arbitrary code embedded in a malicious file. Only load
+           model directories that you created yourself or that come from a
+           source you fully trust.
+        """
         output_path = Path(output_dir)
         with (output_path / "model.pkl").open("rb") as handle:
             payload = pickle.load(handle)