diff --git a/server_files/model.php b/server_files/model.php
index 1f73cfd..bb8f2ff 100644
--- a/server_files/model.php
+++ b/server_files/model.php
@@ -155,7 +155,9 @@ function getZipFile($problem, $team_id = -1)
 	foreach ($data as $file) {
 		$file_id = $file->getFileId();
 		$user = User::fromId($file->getUserId());
-		$name = "Autorisation de droit à l'image de " . $user->getFirstName() . " " . $user->getSurname() . ".pdf";
+        $mime_type = finfo_file(finfo_open(FILEINFO_MIME_TYPE), "$LOCAL_PATH/files/$file_id");
+        $ext = $mime_type == "application/pdf" ? "pdf" : ($mime_type == "image/png" ? "png" : "jpg");
+		$name = "Autorisation de droit à l'image de " . $user->getFirstName() . " " . $user->getSurname() . "." . $ext;
 
 		$zip->addFile("$LOCAL_PATH/files/$file_id", $name);
 	}