diff --git a/mini_agent/skills/document-skills/docx/ooxml/scripts/validation/redlining.py b/mini_agent/skills/document-skills/docx/ooxml/scripts/validation/redlining.py
index 7ed425e..d9cf150 100644
--- a/mini_agent/skills/document-skills/docx/ooxml/scripts/validation/redlining.py
+++ b/mini_agent/skills/document-skills/docx/ooxml/scripts/validation/redlining.py
@@ -29,7 +29,7 @@ def validate(self):
 
         # First, check if there are any tracked changes by Claude to validate
         try:
-            import xml.etree.ElementTree as ET
+            import defusedxml.etree.ElementTree as ET
 
             tree = ET.parse(modified_file)
             root = tree.getroot()
@@ -81,7 +81,7 @@ def validate(self):
 
             # Parse both XML files using xml.etree.ElementTree for redlining validation
             try:
-                import xml.etree.ElementTree as ET
+                import defusedxml.etree.ElementTree as ET
 
                 modified_tree = ET.parse(modified_file)
                 modified_root = modified_tree.getroot()
diff --git a/mini_agent/skills/document-skills/pptx/ooxml/scripts/validation/redlining.py b/mini_agent/skills/document-skills/pptx/ooxml/scripts/validation/redlining.py
index 7ed425e..7de888b 100644
--- a/mini_agent/skills/document-skills/pptx/ooxml/scripts/validation/redlining.py
+++ b/mini_agent/skills/document-skills/pptx/ooxml/scripts/validation/redlining.py
@@ -29,7 +29,7 @@ def validate(self):
 
         # First, check if there are any tracked changes by Claude to validate
         try:
-            import xml.etree.ElementTree as ET
+            import defusedxml.etree.ElementTree as ET
 
             tree = ET.parse(modified_file)
             root = tree.getroot()
@@ -79,9 +79,9 @@ def validate(self):
                 )
                 return False
 
-            # Parse both XML files using xml.etree.ElementTree for redlining validation
+            # Parse both XML files using defusedxml for redlining validation
             try:
-                import xml.etree.ElementTree as ET
+                import defusedxml.etree.ElementTree as ET
 
                 modified_tree = ET.parse(modified_file)
                 modified_root = modified_tree.getroot()
diff --git a/mini_agent/skills/mcp-builder/scripts/evaluation.py b/mini_agent/skills/mcp-builder/scripts/evaluation.py
index 4177856..7ad6506 100644
--- a/mini_agent/skills/mcp-builder/scripts/evaluation.py
+++ b/mini_agent/skills/mcp-builder/scripts/evaluation.py
@@ -10,7 +10,7 @@
 import sys
 import time
 import traceback
-import xml.etree.ElementTree as ET
+import defusedxml.etree.ElementTree as ET
 from pathlib import Path
 from typing import Any
 
diff --git a/pyproject.toml b/pyproject.toml
index aa22232..60a3a7f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -21,6 +21,7 @@ dependencies = [
     "pipx>=1.8.0",
     "anthropic>=0.39.0",
     "openai>=1.57.4",
+    "defusedxml>=0.7.1",
     "agent-client-protocol>=0.6.0",
 ]