From 6f512f39fb6e8c4078b45ec69239d90311352b91 Mon Sep 17 00:00:00 2001
From: gorhill <rhill@raymondhill.net>
Date: Tue, 8 Nov 2016 16:31:04 -0500
Subject: [PATCH] code review re #2132

---
 src/js/cosmetic-filtering.js | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/js/cosmetic-filtering.js b/src/js/cosmetic-filtering.js
index cc9b7bf4d..bdbc9c638 100644
--- a/src/js/cosmetic-filtering.js
+++ b/src/js/cosmetic-filtering.js
@@ -1419,11 +1419,14 @@ FilterContainer.prototype._lookupUserScript = function(dict, raw, reng, out) {
     var content = reng.resourceContentFromName(token, 'application/javascript');
     if ( !content ) { return; }
     if ( args ) {
-        var i = 1;
+        var i = 1, arg;
         while ( args !== '' ) {
             pos = args.indexOf(',');
             if ( pos === -1 ) { pos = args.length; }
-            content = content.replace('{{' + i + '}}', args.slice(0, pos).trim());
+            arg = args.slice(0, pos).trim();
+            if ( reArgValidator.test(arg) ) {
+                content = content.replace('{{' + i + '}}', arg);
+            }
             args = args.slice(pos + 1).trim();
             i++;
         }
@@ -1432,6 +1435,9 @@ FilterContainer.prototype._lookupUserScript = function(dict, raw, reng, out) {
     out.push(content);
 };
 
+// Only accept plain word characters for now.
+var reArgValidator = /^\w*$/;
+
 /******************************************************************************/
 
 FilterContainer.prototype.toSelfie = function() {