diff --git a/comfy/samplers.py b/comfy/samplers.py
index c508a3a41..d281ecc19 100644
--- a/comfy/samplers.py
+++ b/comfy/samplers.py
@@ -12,7 +12,6 @@ import collections
 from comfy import model_management
 import math
 import logging
-import comfy.samplers
 import comfy.sampler_helpers
 import comfy.model_patcher
 import comfy.patcher_extension
@@ -178,7 +177,7 @@ def finalize_default_conds(model: 'BaseModel', hooked_to_run: dict[comfy.hooks.H
         cond = default_conds[i]
         for x in cond:
             # do get_area_and_mult to get all the expected values
-            p = comfy.samplers.get_area_and_mult(x, x_in, timestep)
+            p = get_area_and_mult(x, x_in, timestep)
             if p is None:
                 continue
             # replace p's mult with calculated mult
@@ -215,7 +214,7 @@ def _calc_cond_batch(model: 'BaseModel', conds: list[list[dict]], x_in: torch.Te
                     default_c.append(x)
                     has_default_conds = True
                     continue
-                p = comfy.samplers.get_area_and_mult(x, x_in, timestep)
+                p = get_area_and_mult(x, x_in, timestep)
                 if p is None:
                     continue
                 if p.hooks is not None:
diff --git a/server.py b/server.py
index bae898ef5..88c163fc7 100644
--- a/server.py
+++ b/server.py
@@ -329,6 +329,9 @@ class PromptServer():
                 original_ref = json.loads(post.get("original_ref"))
                 filename, output_dir = folder_paths.annotated_filepath(original_ref['filename'])
 
+                if not filename:
+                    return web.Response(status=400)
+
                 # validation for security: prevent accessing arbitrary path
                 if filename[0] == '/' or '..' in filename:
                     return web.Response(status=400)
@@ -370,6 +373,9 @@ class PromptServer():
                 filename = request.rel_url.query["filename"]
                 filename,output_dir = folder_paths.annotated_filepath(filename)
 
+                if not filename:
+                    return web.Response(status=400)
+
                 # validation for security: prevent accessing arbitrary path
                 if filename[0] == '/' or '..' in filename:
                     return web.Response(status=400)