diff --git a/src/wp-admin/includes/class-wp-filesystem-ftpext.php b/src/wp-admin/includes/class-wp-filesystem-ftpext.php
index c869ec0dc9..7f5f052cbb 100644
--- a/src/wp-admin/includes/class-wp-filesystem-ftpext.php
+++ b/src/wp-admin/includes/class-wp-filesystem-ftpext.php
@@ -520,8 +520,9 @@ class WP_Filesystem_FTPext extends WP_Filesystem_Base {
 		}
 
 		// Replace symlinks formatted as "source -> target" with just the source name
-		if ( $b['islink'] )
+		if ( isset( $b['islink'] ) && $b['islink'] ) {
 			$b['name'] = preg_replace( '/(\s*->\s*.*)$/', '', $b['name'] );
+		}
 
 		return $b;
 	}