diff --git a/htdocs/core/class/html.formfile.class.php b/htdocs/core/class/html.formfile.class.php
index 441ddb60255..05489c3dc50 100644
--- a/htdocs/core/class/html.formfile.class.php
+++ b/htdocs/core/class/html.formfile.class.php
@@ -1471,10 +1471,10 @@ class FormFile
 							if ($nboffiles > 1 && $conf->browser->layout != 'phone') {
 								print '<td class="linecolmove tdlineupdown center">';
 								if ($i > 0) {
-									print '<a class="lineupdown" href="'.$_SERVER["PHP_SELF"].'?id='.$this->id.'&action=up&rowid='.$line->id.'">'.img_up('default', 0, 'imgupforline').'</a>';
+									print '<a class="lineupdown" href="'.$_SERVER["PHP_SELF"].'?id='.$object->id.'&action=up&rowid='.$object->id.'">'.img_up('default', 0, 'imgupforline').'</a>';
 								}
 								if ($i < ($nboffiles - 1)) {
-									print '<a class="lineupdown" href="'.$_SERVER["PHP_SELF"].'?id='.$this->id.'&action=down&rowid='.$line->id.'">'.img_down('default', 0, 'imgdownforline').'</a>';
+									print '<a class="lineupdown" href="'.$_SERVER["PHP_SELF"].'?id='.$object->id.'&action=down&rowid='.$object->id.'">'.img_down('default', 0, 'imgdownforline').'</a>';
 								}
 								print '</td>';
 							} else {