diff --git a/files/class-vip-filesystem-local-stream-wrapper.php b/files/class-vip-filesystem-local-stream-wrapper.php
index cca388310a..c0fb026a61 100644
--- a/files/class-vip-filesystem-local-stream-wrapper.php
+++ b/files/class-vip-filesystem-local-stream-wrapper.php
@@ -129,6 +129,13 @@ class VIP_Filesystem_Local_Stream_Wrapper {
 	 */
 	private static $local_file_patterns = array();
 
+	/**
+	 * HashMap of filename substrings for local files
+	 *
+	 * @var array
+	 */
+	private static $local_file_names = array();
+
 	/**
 	 * File handle for local files
 	 *
@@ -1152,6 +1159,8 @@ public static function add_local_file( $file_path ) {
 
 		if ( $is_pattern ) {
 			static::$local_file_patterns[ $file_path ] = true;
+		} elseif ( false === strpos( $file_path, '/' ) ) {
+			static::$local_file_names[ $file_path ] = true;
 		} else {
 			static::$local_files_map[ $file_path ] = true;
 		}
@@ -1168,16 +1177,17 @@ public static function add_local_file( $file_path ) {
 	public static function remove_local_file( $file_path ) {
 		unset( static::$local_file_patterns[ $file_path ] );
 		unset( static::$local_files_map[ $file_path ] );
+		unset( static::$local_file_names[ $file_path ] );
 		return true;
 	}
 
 	/**
 	 * Get the list of files that should be handled locally
 	 *
-	 * @return array List of file paths and patterns
+	 * @return array List of file paths, patterns and file names
 	 */
 	public static function get_local_files() {
-		return array_merge( static::$local_files_map, static::$local_file_patterns );
+		return array_merge( static::$local_files_map, static::$local_file_patterns, static::$local_file_names );
 	}
 
 	/**
@@ -1192,6 +1202,14 @@ public static function is_local_file( $file_path ) {
 			return true;
 		}
 
+		// Check if any filename substring is present in the filename.
+		$file_name = \wp_basename( $file_path );
+		foreach ( static::$local_file_names as $name => $value ) {
+			if ( false !== strpos( $file_name, $name ) ) {
+				return true;
+			}
+		}
+
 		// Check against wildcard patterns
 		foreach ( static::$local_file_patterns as $pattern => $value ) {
 			if ( fnmatch( $pattern, $file_path, FNM_PATHNAME ) ) {
diff --git a/tests/files/test-vip-filesystem-local-stream-wrapper.php b/tests/files/test-vip-filesystem-local-stream-wrapper.php
index 3c80953e7b..dbabb0a08f 100644
--- a/tests/files/test-vip-filesystem-local-stream-wrapper.php
+++ b/tests/files/test-vip-filesystem-local-stream-wrapper.php
@@ -478,6 +478,18 @@ public function test_lookup_optimization() {
 		}
 	}
 
+	public function test_filename_substring_matching() {
+		$this->assertFalse( VIP_Filesystem_Local_Stream_Wrapper::is_local_file( 'vip://wp-content/uploads/.htaccess' ) );
+
+		VIP_Filesystem_Local_Stream_Wrapper::add_local_file( '.htaccess' );
+		$this->assertTrue( VIP_Filesystem_Local_Stream_Wrapper::is_local_file( 'vip://wp-content/uploads/.htaccess' ) );
+		$this->assertTrue( VIP_Filesystem_Local_Stream_Wrapper::is_local_file( 'vip://wp-content/uploads/cache/.htaccess.backup' ) );
+		$this->assertFalse( VIP_Filesystem_Local_Stream_Wrapper::is_local_file( 'vip://wp-content/uploads/cache/htaccess.txt' ) );
+
+		VIP_Filesystem_Local_Stream_Wrapper::remove_local_file( '.htaccess' );
+		$this->assertFalse( VIP_Filesystem_Local_Stream_Wrapper::is_local_file( 'vip://wp-content/uploads/.htaccess' ) );
+	}
+
 	public function test__global_helpers__add() {
 		// Add files using the global helper
 		$result = wpvip_fs_local_file_add( 'vip://wp-content/uploads/direct.txt' );