Merge branch 'master' into restock-value-template-fix

changedetectionio/flask_app.py

@@ -712,8 +712,29 @@ def changedetection_app(config=None, datastore_o=None):
     def static_content(group, filename):
         from flask import make_response
         import re
-        group = re.sub(r'[^\w.-]+', '', group.lower())
-        filename = re.sub(r'[^\w.-]+', '', filename.lower())
+        def sanitize_filename(filename):
+            filename = filename.lower()
+
+            # Split extension
+            name, ext = os.path.splitext(filename)
+
+            # Remove unwanted chars from name and extension
+            name = re.sub(r'[^a-z0-9_]+', '', name)
+            ext = re.sub(r'[^a-z0-9]+', '', ext.lstrip('.'))
+
+            if not name:
+                raise ValueError("Invalid filename")
+
+            # Rebuild with at most one dot
+            return f"{name}.{ext}" if ext else name
+
+        # Strict sanitization: only allow a-z, 0-9, and underscore (blocks .. and other traversal)
+        group = re.sub(r'[^a-z0-9_]+', '', group.lower())
+        filename = sanitize_filename(filename)
+
+        # Additional safety: reject if sanitization resulted in empty strings
+        if not group or not filename:
+            abort(404)
 
         if group == 'screenshot':
             # Could be sensitive, follow password requirements

changedetectionio/store/__init__.py

@@ -235,6 +235,8 @@ class ChangeDetectionStore(DatastoreUpdatesMixin, FileSavingDataStore):
             # No datastore yet - check if this is a fresh install or legacy migration
             self.init_fresh_install(include_default_watches=include_default_watches,
                                     version_tag=version_tag)
+            # Maybe they copied a bunch of watch subdirs across too
+            self._load_state()
 
     def init_fresh_install(self, include_default_watches, version_tag):
       # Generate app_guid FIRST (required for all operations)

changedetectionio/tests/test_security.py

@@ -478,3 +478,80 @@ def test_logout_with_redirect(client, live_server, measure_memory_usage, datasto
     # Cleanup
     del client.application.config['DATASTORE'].data['settings']['application']['password']
 
+
+def test_static_directory_traversal(client, live_server, measure_memory_usage, datastore_path):
+    """
+    Test that the static file serving route properly blocks directory traversal attempts.
+    This tests the fix for GHSA-9jj8-v89v-xjvw (CVE pending).
+
+    The vulnerability was in /static/<group>/<filename> where the sanitization regex
+    allowed dots, enabling "../" traversal to read application source files.
+
+    The fix changed the regex from r'[^\w.-]+' to r'[^a-z0-9_]+' which blocks dots.
+    """
+
+    # Test 1: Direct .. traversal attempt (URL-encoded)
+    res = client.get(
+        "/static/%2e%2e/flask_app.py",
+        follow_redirects=False
+    )
+    # Should be blocked (404 or 403)
+    assert res.status_code in [404, 403], f"Expected 404/403, got {res.status_code}"
+    # Should NOT contain application source code
+    assert b"def static_content" not in res.data
+    assert b"changedetection_app" not in res.data
+
+    # Test 2: Direct .. traversal attempt (unencoded)
+    res = client.get(
+        "/static/../flask_app.py",
+        follow_redirects=False
+    )
+    assert res.status_code in [404, 403], f"Expected 404/403, got {res.status_code}"
+    assert b"def static_content" not in res.data
+
+    # Test 3: Multiple dots traversal
+    res = client.get(
+        "/static/..../flask_app.py",
+        follow_redirects=False
+    )
+    assert res.status_code in [404, 403], f"Expected 404/403, got {res.status_code}"
+    assert b"def static_content" not in res.data
+
+    # Test 4: Try to access other application files
+    for filename in ["__init__.py", "datastore.py", "store.py"]:
+        res = client.get(
+            f"/static/%2e%2e/{filename}",
+            follow_redirects=False
+        )
+        assert res.status_code in [404, 403], f"File {filename} should be blocked"
+        # Should not contain Python code indicators
+        assert b"import" not in res.data or b"# Test" in res.data  # Allow "1 Imported" etc
+
+    # Test 5: Verify legitimate static files still work
+    # Note: We can't test actual files without knowing what exists,
+    # but we can verify the sanitization doesn't break valid groups
+    res = client.get(
+        "/static/images/test.png",  # Will 404 if file doesn't exist, but won't traverse
+        follow_redirects=False
+    )
+    # Should get 404 (file not found) not 403 (blocked)
+    # This confirms the group name "images" is valid
+    assert res.status_code == 404
+
+    # Test 6: Ensure hyphens and dots are blocked in group names
+    res = client.get(
+        "/static/../../../etc/passwd",
+        follow_redirects=False
+    )
+    assert res.status_code in [404, 403]
+    assert b"root:" not in res.data
+
+    # Test 7: Test that underscores still work (they're allowed)
+    res = client.get(
+        "/static/visual_selector_data/test.json",
+        follow_redirects=False
+    )
+    # visual_selector_data is a real group, but requires auth
+    # Should get 403 (not authenticated) or 404 (file not found), not a path traversal
+    assert res.status_code in [403, 404]
+