diff --git a/include/class.pdf.php b/include/class.pdf.php
index 8346ee3c735a43de303008670fe9e3b6fb101e3d..7c5e6b775d8455d33b5489d67f685a6955dcbdb9 100644
--- a/include/class.pdf.php
+++ b/include/class.pdf.php
@@ -56,7 +56,7 @@ class Ticket2PDF extends mPDF
             return INCLUDE_DIR.'fpdf/print-logo.png';
         }
 
-        $tmp = tempnam("", 'pdf') . '.jpg';
+        $tmp = tempnam(sys_get_temp_dir(), 'pdf') . '.jpg';
         $img = imagecreatefromstring($logo->getData());
         // Handle transparent images with white background
         $img2 = imagecreatetruecolor(imagesx($img), imagesy($img));