diff --git a/comfy_execution/caching.py b/comfy_execution/caching.py
index 2169dda9a..08f3f436b 100644
--- a/comfy_execution/caching.py
+++ b/comfy_execution/caching.py
@@ -155,13 +155,14 @@ def _sanitize_signature_input(obj, depth=0, max_depth=_MAX_SIGNATURE_DEPTH, acti
     try:
         if obj_type is dict:
             try:
+                items = list(obj.items())
                 sort_memo = {}
                 sanitized_items = [
                     (
                         _sanitize_signature_input(key, depth + 1, max_depth, active, memo, budget),
                         _sanitize_signature_input(value, depth + 1, max_depth, active, memo, budget),
                     )
-                    for key, value in obj.items()
+                    for key, value in items
                 ]
                 ordered_items = [
                     (
@@ -187,22 +188,26 @@ def _sanitize_signature_input(obj, depth=0, max_depth=_MAX_SIGNATURE_DEPTH, acti
                 result = Unhashable()
         elif obj_type is list:
             try:
-                result = [_sanitize_signature_input(item, depth + 1, max_depth, active, memo, budget) for item in obj]
+                items = list(obj)
+                result = [_sanitize_signature_input(item, depth + 1, max_depth, active, memo, budget) for item in items]
             except RuntimeError:
                 result = Unhashable()
         elif obj_type is tuple:
             try:
-                result = tuple(_sanitize_signature_input(item, depth + 1, max_depth, active, memo, budget) for item in obj)
+                items = list(obj)
+                result = tuple(_sanitize_signature_input(item, depth + 1, max_depth, active, memo, budget) for item in items)
             except RuntimeError:
                 result = Unhashable()
         elif obj_type is set:
             try:
-                result = {_sanitize_signature_input(item, depth + 1, max_depth, active, memo, budget) for item in obj}
+                items = list(obj)
+                result = {_sanitize_signature_input(item, depth + 1, max_depth, active, memo, budget) for item in items}
             except RuntimeError:
                 result = Unhashable()
         else:
             try:
-                result = frozenset(_sanitize_signature_input(item, depth + 1, max_depth, active, memo, budget) for item in obj)
+                items = list(obj)
+                result = frozenset(_sanitize_signature_input(item, depth + 1, max_depth, active, memo, budget) for item in items)
             except RuntimeError:
                 result = Unhashable()
     finally:
diff --git a/tests-unit/execution_test/caching_test.py b/tests-unit/execution_test/caching_test.py
index c9892304a..6313faed1 100644
--- a/tests-unit/execution_test/caching_test.py
+++ b/tests-unit/execution_test/caching_test.py
@@ -105,6 +105,48 @@ def test_sanitize_signature_input_handles_shared_builtin_substructures(caching_m
     assert sanitized[0][1]["value"] == 2
 
 
+def test_sanitize_signature_input_snapshots_list_before_recursing(caching_module, monkeypatch):
+    """List sanitization should read a point-in-time snapshot before recursive descent."""
+    caching, _ = caching_module
+    original = caching._sanitize_signature_input
+    marker = object()
+    values = [marker, 2]
+
+    def mutating_sanitize(obj, *args, **kwargs):
+        """Mutate the live list during recursion to verify snapshot-based traversal."""
+        if obj is marker:
+            values[1] = 3
+        return original(obj, *args, **kwargs)
+
+    monkeypatch.setattr(caching, "_sanitize_signature_input", mutating_sanitize)
+
+    sanitized = original(values)
+
+    assert isinstance(sanitized, list)
+    assert sanitized[1] == 2
+
+
+def test_sanitize_signature_input_snapshots_dict_before_recursing(caching_module, monkeypatch):
+    """Dict sanitization should read a point-in-time snapshot before recursive descent."""
+    caching, _ = caching_module
+    original = caching._sanitize_signature_input
+    marker = object()
+    values = {"first": marker, "second": 2}
+
+    def mutating_sanitize(obj, *args, **kwargs):
+        """Mutate the live dict during recursion to verify snapshot-based traversal."""
+        if obj is marker:
+            values["second"] = 3
+        return original(obj, *args, **kwargs)
+
+    monkeypatch.setattr(caching, "_sanitize_signature_input", mutating_sanitize)
+
+    sanitized = original(values)
+
+    assert isinstance(sanitized, dict)
+    assert sanitized["second"] == 2
+
+
 @pytest.mark.parametrize(
     "container_factory",
     [