diff --git a/backend/endpoints/roms/__init__.py b/backend/endpoints/roms/__init__.py
index 40ca24feb..f4848e0c6 100644
--- a/backend/endpoints/roms/__init__.py
+++ b/backend/endpoints/roms/__init__.py
@@ -1282,7 +1282,7 @@ async def update_rom(
             path_screenshots = await fs_resource_handler.get_rom_screenshots(
                 rom=rom,
                 overwrite=bool(screenshots_changed),
-                url_screenshots=cleaned_data.get("url_screenshots", []),
+                url_screenshots=[add_ss_auth_to_url(u) for u in url_screenshots],
             )
             cleaned_data.update(
                 {"path_screenshots": path_screenshots, "url_screenshots": []}
@@ -1353,7 +1353,7 @@ async def update_rom(
                 path_cover_s, path_cover_l = await fs_resource_handler.get_cover(
                     entity=rom,
                     overwrite=url_cover != rom.url_cover,
-                    url_cover=str(url_cover),
+                    url_cover=add_ss_auth_to_url(str(url_cover)),
                 )
                 cleaned_data.update(
                     {
@@ -1373,7 +1373,7 @@ async def update_rom(
         path_manual = await fs_resource_handler.get_manual(
             rom=rom,
             overwrite=url_manual != rom.url_manual,
-            url_manual=str(url_manual) if url_manual else None,
+            url_manual=add_ss_auth_to_url(str(url_manual)) if url_manual else None,
         )
         cleaned_data.update(
             {
diff --git a/backend/endpoints/sockets/scan.py b/backend/endpoints/sockets/scan.py
index 456ebd7d3..908682440 100644
--- a/backend/endpoints/sockets/scan.py
+++ b/backend/endpoints/sockets/scan.py
@@ -396,13 +396,21 @@ async def _identify_rom(
     path_cover_s, path_cover_l = await fs_resource_handler.get_cover(
         entity=_added_rom,
         overwrite=_added_rom.url_cover != rom.url_cover,
-        url_cover=_added_rom.url_cover,
+        url_cover=(
+            add_ss_auth_to_url(_added_rom.url_cover)
+            if _added_rom.url_cover
+            else _added_rom.url_cover
+        ),
     )
 
     path_manual = await fs_resource_handler.get_manual(
         rom=_added_rom,
         overwrite=_added_rom.url_manual != rom.url_manual,
-        url_manual=_added_rom.url_manual,
+        url_manual=(
+            add_ss_auth_to_url(_added_rom.url_manual)
+            if _added_rom.url_manual
+            else _added_rom.url_manual
+        ),
     )
 
     screenshots_changed = pydash.xor(
@@ -411,7 +419,9 @@ async def _identify_rom(
     path_screenshots = await fs_resource_handler.get_rom_screenshots(
         rom=_added_rom,
         overwrite=bool(screenshots_changed),
-        url_screenshots=_added_rom.url_screenshots,
+        url_screenshots=[
+            add_ss_auth_to_url(u) for u in (_added_rom.url_screenshots or [])
+        ],
     )
 
     _added_rom.path_cover_s = path_cover_s
diff --git a/backend/handler/metadata/ss_handler.py b/backend/handler/metadata/ss_handler.py
index 2ab2b3797..a80628a03 100644
--- a/backend/handler/metadata/ss_handler.py
+++ b/backend/handler/metadata/ss_handler.py
@@ -34,8 +34,17 @@ from .base_handler import (
 SENSITIVE_KEYS = {"ssid", "sspassword"}
 
 
+SS_DOMAIN = "screenscraper.fr"
+
+
 def add_ss_auth_to_url(url: str) -> str:
-    """Re-add SS user credentials to a media URL at download time (never stored)."""
+    """Re-add SS user credentials to a media URL at download time (never stored).
+
+    Only injects credentials for screenscraper.fr URLs; returns other URLs
+    unchanged to avoid leaking credentials to third-party sources.
+    """
+    if not url or SS_DOMAIN not in url:
+        return url
     if not SCREENSCRAPER_USER or not SCREENSCRAPER_PASSWORD:
         return url
 
diff --git a/backend/handler/scan_handler.py b/backend/handler/scan_handler.py
index afe659a67..c7e3d3fbf 100644
--- a/backend/handler/scan_handler.py
+++ b/backend/handler/scan_handler.py
@@ -1045,7 +1045,7 @@ async def scan_rom(
         extra=LOGGER_MODULE_NAME,
     )
 
-    if rom.has_nested_single_file or rom.has_multiple_files:
+    if fs_rom["nested"]:
         for file in fs_rom["files"]:
             log.info(
                 f"\t · {hl(file.file_name, color=LIGHTYELLOW)}",