From b3d388c234327ec226e1ddfca29a8bf00ecea50f Mon Sep 17 00:00:00 2001
From: Tim Hunt <T.J.Hunt@open.ac.uk>
Date: Tue, 24 Feb 2015 17:35:32 +0000
Subject: [PATCH] MDL-49284 formslib: fix strict validation of HTML.

---
 lib/formslib.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/formslib.php b/lib/formslib.php
index b6f0c179a16..88564a784ad 100644
--- a/lib/formslib.php
+++ b/lib/formslib.php
@@ -2905,7 +2905,7 @@ class MoodleQuickForm_Rule_Required extends HTML_QuickForm_Rule {
         global $CFG;
         if (!empty($CFG->strictformsrequired)) {
             if (!empty($format) && $format == FORMAT_HTML) {
-                return array('', "{jsVar}.replace(/(<[^img|hr|canvas]+>)|&nbsp;|\s+/ig, '') == ''");
+                return array('', "{jsVar}.replace(/(<(?!img|hr|canvas)[^>]*>)|&nbsp;|\s+/ig, '') == ''");
             } else {
                 return array('', "{jsVar}.replace(/^\s+$/g, '') == ''");
             }