diff --git a/src/zenzic/cli/_governance.py b/src/zenzic/cli/_governance.py
index 211ad3a..1c58df9 100644
--- a/src/zenzic/cli/_governance.py
+++ b/src/zenzic/cli/_governance.py
@@ -113,9 +113,9 @@ def count_per_file_ignores(config: ZenzicConfig) -> int:
         if not isinstance(codes, list):
             continue
         normalized_codes = {
-            str(code).upper().strip()
+            str(code).strip().upper()
             for code in codes
-            if isinstance(code, str) and str(code).upper().startswith("Z")
+            if isinstance(code, str) and str(code).strip().upper().startswith("Z")
         }
         total += len(normalized_codes)
     return total
diff --git a/src/zenzic/core/suppressions.py b/src/zenzic/core/suppressions.py
index 85e2b95..9dc1559 100644
--- a/src/zenzic/core/suppressions.py
+++ b/src/zenzic/core/suppressions.py
@@ -102,12 +102,11 @@ def is_suppressed(self, line_no: int, code: str) -> bool:
                     self.global_tracker.mark_directory_policy_used(pattern, code)
             return True
 
-        suppressed = False
         for d in self.directives:
-            if d.line_no == line_no and d.code == code:
+            if d.line_no == line_no and d.code == code and not d.consumed:
                 d.consumed = True
-                suppressed = True
-        return suppressed
+                return True
+        return False
 
     def get_dead_suppressions(self) -> list["RuleFinding"]:
         """Yield Z603 findings for all directives that were never consumed."""
@@ -146,7 +145,7 @@ def __init__(self, config: "ZenzicConfig"):
         if getattr(config, "governance", None) and config.governance.directory_policies:
             for pattern, codes in config.governance.directory_policies.items():
                 for code in codes:
-                    self.unused_dir_policies.add((pattern, str(code).upper()))
+                    self.unused_dir_policies.add((pattern, str(code).strip().upper()))
 
         if getattr(config, "excluded_file_patterns", None):
             for pattern in config.excluded_file_patterns:
diff --git a/src/zenzic/models/config.py b/src/zenzic/models/config.py
index 4d10424..90416aa 100644
--- a/src/zenzic/models/config.py
+++ b/src/zenzic/models/config.py
@@ -704,11 +704,12 @@ def _validate_no_swallowed_root_keys(data: dict[str, Any]) -> None:
             tables_to_check = []
             if isinstance(value, dict):
                 tables_to_check.append(value)
-            elif isinstance(value, list) and value and isinstance(value[0], dict):
-                tables_to_check.extend(value)
+            elif isinstance(value, list) and value:
+                tables_to_check.extend(item for item in value if isinstance(item, dict))
 
             for table in tables_to_check:
-                swallowed = set(table.keys()) & root_keys
+                if isinstance(table, dict):
+                    swallowed = set(table.keys()) & root_keys
                 if swallowed:
                     from rich.markup import escape
 
diff --git a/tests/test_security.py b/tests/test_security.py
new file mode 100644
index 0000000..4cb7532
--- /dev/null
+++ b/tests/test_security.py
@@ -0,0 +1,61 @@
+# SPDX-FileCopyrightText: 2026 PythonWoods <dev@pythonwoods.dev>
+# SPDX-License-Identifier: Apache-2.0
+"""Security and robustness tests for Zenzic core."""
+
+from __future__ import annotations
+
+from pathlib import Path
+import pytest
+
+from zenzic.models.config import ZenzicConfig
+from zenzic.cli._governance import count_per_file_ignores
+from zenzic.core.suppressions import SuppressionTracker
+
+
+def test_ghost_policy_leading_space_remediation() -> None:
+    """Vulnerability 1: Ensure leading/trailing spaces in per_file_ignores are counted in DQS."""
+    config_data = {
+        "governance": {
+            "per_file_ignores": {
+                "docs/index.md": [" Z101"]
+            }
+        }
+    }
+    config = ZenzicConfig(**config_data)
+
+    # Verify the space-prefixed code is properly counted as a suppression
+    per_file_count = count_per_file_ignores(config)
+    assert per_file_count == 1, "The leading-space ignore must be counted as a suppression to avoid DQS bypass"
+
+
+def test_toml_bomb_mixed_type_array_remediation() -> None:
+    """Vulnerability 2: Ensure mixed-type arrays in configuration tables do not crash the swallowed root validator."""
+    data = {
+        "custom_rules": [
+            {"id": "ZZ-TEST", "pattern": "test", "message": "test"},
+            42
+        ]
+    }
+
+    # This should not raise an AttributeError crash
+    try:
+        ZenzicConfig._validate_no_swallowed_root_keys(data)
+    except AttributeError:
+        pytest.fail("Swallowed root validator crashed on mixed-type array item.")
+
+
+def test_duplicate_inline_suppressions_remediation() -> None:
+    """Vulnerability 3: Ensure duplicate inline suppressions are not fully consumed by a single finding."""
+    # We have two ignore comments for Z101 on line 1, but only one Z101 finding
+    text = "<!-- zenzic:ignore: Z101 --> <!-- zenzic:ignore: Z101 -->\n"
+    tracker = SuppressionTracker(Path("dummy.md"), text)
+
+    assert len(tracker.directives) == 2
+
+    # First Z101 finding is suppressed and consumes one directive
+    assert tracker.is_suppressed(1, "Z101")
+
+    # One of the two Z101 directives should be dead (unconsumed)
+    dead = tracker.get_dead_suppressions()
+    assert len(dead) == 1, "The duplicate inline ignore must remain unconsumed and trigger Z603"
+    assert dead[0].rule_id == "Z603"