diff --git a/backend/handler/filesystem/base_handler.py b/backend/handler/filesystem/base_handler.py
index 61a1fe13f..61b1c122c 100644
--- a/backend/handler/filesystem/base_handler.py
+++ b/backend/handler/filesystem/base_handler.py
@@ -205,6 +205,19 @@ class FSHandler:
         match = EXTENSION_REGEX.search(file_name)
         return match.group(1) if match else ""
 
+    def iter_file_extensions(self, file_name: str) -> list[str]:
+        """Return all right-anchored sub-extensions for a filename.
+
+        For "game.nds.enc.hash.txt" this yields:
+            ["nds.enc.hash.txt", "enc.hash.txt", "hash.txt", "txt"]
+        This allows exclusion rules like "hash.txt" to match multi-dot filenames.
+        """
+        ext = self.parse_file_extension(file_name)
+        if not ext:
+            return []
+        parts = ext.split(".")
+        return [".".join(parts[i:]) for i in range(len(parts))]
+
     def extract_uuid_v4_from_filename(self, file_name: str) -> str:
         match = UUID_V4_REGEX.search(file_name)
         return match.group(0) if match else ""
@@ -215,16 +228,11 @@ class FSHandler:
         excluded_files: list[str] = []
 
         for file_name in files:
-            # Get the compound extension (e.g. "nds.hash.txt" for "game.nds.hash.txt")
-            # and the last single extension (e.g. "txt") for multi-dot filenames.
-            ext = self.parse_file_extension(file_name)
-            suffix = Path(file_name).suffix.lstrip(".")
-
-            # Exclude the file if the compound extension or the last single extension
-            # is in the excluded list. Checking both handles files with multiple dots
-            # (e.g. "game.nds.hash.txt" should be excluded when "txt" is excluded).
-            if (ext and ext.lower() in excluded_extensions) or (
-                suffix and suffix.lower() in excluded_extensions
+            # Check all right-anchored sub-extensions so that rules like "hash.txt"
+            # match multi-dot filenames such as "game.nds.enc.hash.txt".
+            if any(
+                e.lower() in excluded_extensions
+                for e in self.iter_file_extensions(file_name)
             ):
                 excluded_files.append(file_name)
 
diff --git a/backend/handler/filesystem/roms_handler.py b/backend/handler/filesystem/roms_handler.py
index 6b6d36c74..90f0aa0c8 100644
--- a/backend/handler/filesystem/roms_handler.py
+++ b/backend/handler/filesystem/roms_handler.py
@@ -456,12 +456,11 @@ class FSRomsHandler(FSHandler):
                 f"{abs_fs_path}/{rom.fs_name}", recursive=True
             ):
                 # Check if file is excluded by extension.
-                # Also check the last single extension for multi-dot filenames
-                # (e.g. "game.nds.hash.txt" should be excluded when "txt" is excluded).
-                ext = self.parse_file_extension(file_name)
-                suffix = Path(file_name).suffix.lstrip(".")
-                if (ext and ext.lower() in excluded_file_exts) or (
-                    suffix and suffix.lower() in excluded_file_exts
+                # Check all right-anchored sub-extensions so that rules like "hash.txt"
+                # match multi-dot filenames such as "game.nds.enc.hash.txt".
+                if any(
+                    e.lower() in excluded_file_exts
+                    for e in self.iter_file_extensions(file_name)
                 ):
                     continue
 
diff --git a/backend/tests/handler/filesystem/test_base_handler.py b/backend/tests/handler/filesystem/test_base_handler.py
index 3dd59dd96..5d9e329d4 100644
--- a/backend/tests/handler/filesystem/test_base_handler.py
+++ b/backend/tests/handler/filesystem/test_base_handler.py
@@ -145,6 +145,22 @@ class TestFSHandler:
         assert handler.parse_file_extension("no_extension") == ""
         assert handler.parse_file_extension("file.with.dots.txt") == "with.dots.txt"
 
+    def test_iter_file_extensions(self, handler: FSHandler):
+        """Test that all right-anchored sub-extensions are returned"""
+        assert handler.iter_file_extensions("game.nds") == ["nds"]
+        assert handler.iter_file_extensions("game.nds.hash.txt") == [
+            "nds.hash.txt",
+            "hash.txt",
+            "txt",
+        ]
+        assert handler.iter_file_extensions("game.nds.enc.hash.txt") == [
+            "nds.enc.hash.txt",
+            "enc.hash.txt",
+            "hash.txt",
+            "txt",
+        ]
+        assert handler.iter_file_extensions("no_extension") == []
+
     def test_exclude_single_files(self, handler: FSHandler):
         """Test file exclusion functionality"""
         files = ["test.txt", "game.rom", "excluded.tmp", "data.json"]
@@ -162,7 +178,7 @@ class TestFSHandler:
             assert "data.json" in result
 
     def test_exclude_single_files_multi_dot(self, handler: FSHandler):
-        """Test that files with multiple dots are excluded based on their last extension"""
+        """Test that files with multiple dots are excluded by last or compound extension"""
         files = [
             "game.nds",
             "game.nds.hash.txt",
@@ -172,17 +188,29 @@ class TestFSHandler:
         ]
 
         with patch("handler.filesystem.base_handler.cm.get_config") as mock_config:
+            # Exclude by last single extension
             mock_config.return_value.EXCLUDED_SINGLE_EXT = ["txt"]
             mock_config.return_value.EXCLUDED_SINGLE_FILES = []
 
             result = handler.exclude_single_files(files)
 
-            # Files with .txt as the last extension should be excluded regardless of
-            # how many dots are in the filename
             assert "game.nds.hash.txt" not in result
             assert "game.nds.enc.hash.txt" not in result
             assert "readme.txt" not in result
-            # Non-txt files should not be excluded
+            assert "game.nds" in result
+            assert "game.rom" in result
+
+        with patch("handler.filesystem.base_handler.cm.get_config") as mock_config:
+            # Exclude by compound sub-extension "hash.txt"
+            mock_config.return_value.EXCLUDED_SINGLE_EXT = ["hash.txt"]
+            mock_config.return_value.EXCLUDED_SINGLE_FILES = []
+
+            result = handler.exclude_single_files(files)
+
+            assert "game.nds.hash.txt" not in result
+            assert "game.nds.enc.hash.txt" not in result
+            # "readme.txt" does NOT end in "hash.txt" — should remain
+            assert "readme.txt" in result
             assert "game.nds" in result
             assert "game.rom" in result