diff --git a/source/blender/nodes/geometry/include/NOD_geo_bundle.hh b/source/blender/nodes/geometry/include/NOD_geo_bundle.hh
index 5f91820f8fd..ec542c1cfc2 100644
--- a/source/blender/nodes/geometry/include/NOD_geo_bundle.hh
+++ b/source/blender/nodes/geometry/include/NOD_geo_bundle.hh
@@ -37,6 +37,8 @@ struct CombineBundleItemsAccessor : public socket_items::SocketItemsAccessorDefa
   static constexpr StringRefNull node_idname = "GeometryNodeCombineBundle";
   static constexpr bool has_type = true;
   static constexpr bool has_name = true;
+  static constexpr bool has_name_validation = true;
+  static constexpr char unique_name_separator = '_';
   struct operator_idnames {
     static constexpr StringRefNull add_item = "NODE_OT_combine_bundle_item_add";
     static constexpr StringRefNull remove_item = "NODE_OT_combine_bundle_item_remove";
@@ -100,6 +102,8 @@ struct CombineBundleItemsAccessor : public socket_items::SocketItemsAccessorDefa
   {
     return "Item_" + std::to_string(item.identifier);
   }
+
+  static std::string validate_name(const StringRef name);
 };
 
 struct SeparateBundleItemsAccessor : public socket_items::SocketItemsAccessorDefaults {
@@ -109,6 +113,8 @@ struct SeparateBundleItemsAccessor : public socket_items::SocketItemsAccessorDef
   static constexpr StringRefNull node_idname = "GeometryNodeSeparateBundle";
   static constexpr bool has_type = true;
   static constexpr bool has_name = true;
+  static constexpr bool has_name_validation = true;
+  static constexpr char unique_name_separator = '_';
   struct operator_idnames {
     static constexpr StringRefNull add_item = "NODE_OT_separate_bundle_item_add";
     static constexpr StringRefNull remove_item = "NODE_OT_separate_bundle_item_remove";
@@ -172,6 +178,11 @@ struct SeparateBundleItemsAccessor : public socket_items::SocketItemsAccessorDef
   {
     return "Item_" + std::to_string(item.identifier);
   }
+
+  static std::string validate_name(const StringRef name)
+  {
+    return CombineBundleItemsAccessor::validate_name(name);
+  }
 };
 
 }  // namespace blender::nodes
diff --git a/source/blender/nodes/geometry/nodes/node_geo_combine_bundle.cc b/source/blender/nodes/geometry/nodes/node_geo_combine_bundle.cc
index 9d4528b39af..e08fa95567e 100644
--- a/source/blender/nodes/geometry/nodes/node_geo_combine_bundle.cc
+++ b/source/blender/nodes/geometry/nodes/node_geo_combine_bundle.cc
@@ -189,4 +189,26 @@ void CombineBundleItemsAccessor::blend_read_data_item(BlendDataReader *reader, I
   BLO_read_string(reader, &item.name);
 }
 
+std::string CombineBundleItemsAccessor::validate_name(const StringRef name)
+{
+  std::string result;
+  if (name.is_empty()) {
+    return result;
+  }
+  /* Disallow certain characters so that we can use them to e.g. build a bundle path or
+   * expressions referencing multiple bundle items. We might not need all of them in the future,
+   * but better reserve them now while we still can. */
+  constexpr StringRefNull forbidden_chars_str = "/*&|\"^~!,{}()+$#@[];:?<>.-%\\=";
+  const Span<char> forbidden_chars = forbidden_chars_str;
+  for (const char c : name) {
+    if (forbidden_chars.contains(c)) {
+      result += '_';
+    }
+    else {
+      result += c;
+    }
+  }
+  return result;
+}
+
 }  // namespace blender::nodes