From 49ed732824aff7cee61727fb2d3526bfa2f0f587 Mon Sep 17 00:00:00 2001
From: Don Mitchell <dmitchell@edx.org>
Date: Mon, 25 Aug 2014 17:00:48 -0400
Subject: [PATCH] JS regex's need to escape special chars LMS-11260

---
 common/static/js/src/utility.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/common/static/js/src/utility.js b/common/static/js/src/utility.js
index ab899711f8..ef540373fc 100644
--- a/common/static/js/src/utility.js
+++ b/common/static/js/src/utility.js
@@ -35,8 +35,9 @@ window.rewriteStaticLinks = function(content, from, to) {
     }
     // change all relative urls only which may be embedded inside other tags in content.
     // handle http and https
-    // note: add other protocols here
-    var regex = new RegExp("(https?:\/\/(www\.)?[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,6}([-a-zA-Z0-9@:%_\+.~#?&//=]*))?"+from, 'g');
+    // escape all regex interpretable chars
+    fromRe = from.replace(/[-\/\\^$*+?.()|[\]{}]/g, '\\$&');
+    var regex = new RegExp("(https?:\/\/(www\.)?[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,6}([-a-zA-Z0-9@:%_\+.~#?&//=]*))?"+fromRe, 'g');
     return content.replace(regex, replacer);
 };