OoO En ce  début de soirée du vendredi 28 décembre  2007, vers 21:45, je
disais:

>> I found Squirrelmail's solution. They seem to use one function for every
>> possible tag in the HTML source:

>> http://osdir.com/ml/mail.squirrelmail.cvs/2006-12/msg00031.html

>> I'll try to implement that, and/or search for more :)

> Hi Robin !

> I noticed  that you have posted  a patch. I  have tried it but  it seems
> that there is no effect. I have tried with ie6 from ie4linux and I still
> get the javascript popups. Did you try it succesfully on rc2?

> I have used the test message from here:
>  http://www.topolis.lt/bugtraq/expression.eml.gz

I have tried with an up-to-date IE7 and the patch provided here does not
fix the issue. In fact, the source code shows there is still unsanitized
strings. I  have completed the  patch with a function  from Squirrelmail
(sq_defang). I have attached the complete patch.

Attachment: pgpLOigAepmuJ.pgp
Description: PGP signature

--- roundcube/program/steps/mail/func.inc	2007-10-17 08:50:28.000000000 +0200
+++ roundcube/program/steps/mail/func.inc	2008-01-22 21:59:30.000000000 +0100
@@ -481,6 +481,124 @@
   return Q($out);
   }
 
+/* Stolen from Squirrelmail */
+function sq_deent(&$attvalue, $regex, $hex=false){
+    $ret_match = false;
+    preg_match_all($regex, $attvalue, $matches);
+    if (is_array($matches) && sizeof($matches[0]) > 0){
+        $repl = Array();
+        for ($i = 0; $i < sizeof($matches[0]); $i++){
+            $numval = $matches[1][$i];
+            if ($hex){
+                $numval = hexdec($numval);
+            }
+            $repl{$matches[0][$i]} = chr($numval);
+        }
+        $attvalue = strtr($attvalue, $repl);
+        return true;
+    } else {
+        return false;
+    }
+}
+
+/* Stolen verbatim from Squirrelmail */
+function sq_defang(&$attvalue){
+    /**
+     * Skip this if there aren't ampersands or backslashes.
+     */
+    if (strpos($attvalue, '&') === false
+        && strpos($attvalue, '\\') === false){
+        return;
+    }
+    $m = false;
+    do {
+        $m = false;
+        $m = $m || sq_deent($attvalue, '/\&#0*(\d+);*/s');
+        $m = $m || sq_deent($attvalue, '/\&#x0*((\d|[a-f])+);*/si', true);
+        $m = $m || sq_deent($attvalue, '/\\\\(\d+)/s', true);
+    } while ($m == true);
+    $attvalue = stripslashes($attvalue);
+}
+
+function rcmail_html_filter($html)
+  {
+  preg_match_all('/<\/?\w+((\s+\w+(\s*=\s*(?:".*?"|\'.*?\'|[^\'">\s]+))?)+\s*|\s*)\/?>/', $html, $tags);
+
+  /* From Squirrelmail: Translate all dangerous Unicode or Shift_JIS characters which are accepted by
+   * IE as regular characters. */
+  $replace = array(array('&#x029F;', '&#0671;' ,/* L UNICODE IPA Extension */
+                         '&#x0280;', '&#0640;' ,/* R UNICODE IPA Extension */
+                         '&#x0274;', '&#0628;' ,/* N UNICODE IPA Extension */
+                         '&#xFF25;', '&#65317;' ,/* Unicode FULLWIDTH LATIN CAPITAL LETTER E */
+                         '&#xFF45;', '&#65349;' ,/* Unicode FULLWIDTH LATIN SMALL LETTER E */
+                         '&#xFF38;', '&#65336;',/* Unicode FULLWIDTH LATIN CAPITAL LETTER X */
+                         '&#xFF58;', '&#65368;',/* Unicode FULLWIDTH LATIN SMALL LETTER X */
+                         '&#xFF30;', '&#65328;',/* Unicode FULLWIDTH LATIN CAPITAL LETTER P */
+                         '&#xFF50;', '&#65360;',/* Unicode FULLWIDTH LATIN SMALL LETTER P */
+                         '&#xFF32;', '&#65330;',/* Unicode FULLWIDTH LATIN CAPITAL LETTER R */
+                         '&#xFF52;', '&#65362;',/* Unicode FULLWIDTH LATIN SMALL LETTER R */
+                         '&#xFF33;', '&#65331;',/* Unicode FULLWIDTH LATIN CAPITAL LETTER S */
+                         '&#xFF53;', '&#65363;',/* Unicode FULLWIDTH LATIN SMALL LETTER S */
+                         '&#xFF29;', '&#65321;',/* Unicode FULLWIDTH LATIN CAPITAL LETTER I */
+                         '&#xFF49;', '&#65353;',/* Unicode FULLWIDTH LATIN SMALL LETTER I */
+                         '&#xFF2F;', '&#65327;',/* Unicode FULLWIDTH LATIN CAPITAL LETTER O */
+                         '&#xFF4F;', '&#65359;',/* Unicode FULLWIDTH LATIN SMALL LETTER O */
+                         '&#xFF2E;', '&#65326;',/* Unicode FULLWIDTH LATIN CAPITAL LETTER N */
+                         '&#xFF4E;', '&#65358;',/* Unicode FULLWIDTH LATIN SMALL LETTER N */
+                         '&#xFF2C;', '&#65324;',/* Unicode FULLWIDTH LATIN CAPITAL LETTER L */
+                         '&#xFF4C;', '&#65356;',/* Unicode FULLWIDTH LATIN SMALL LETTER L */
+                         '&#xFF35;', '&#65333;',/* Unicode FULLWIDTH LATIN CAPITAL LETTER U */
+                         '&#xFF55;', '&#65365;',/* Unicode FULLWIDTH LATIN SMALL LETTER U */
+                         '&#x207F;', '&#8319;' ,/* Unicode SUPERSCRIPT LATIN SMALL LETTER N */
+                         "\xEF\xBC\xA5", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER E */
+                                         /* in unicode this is some Chinese char range */
+                         "\xEF\xBD\x85", /* Shift JIS FULLWIDTH LATIN SMALL LETTER E */
+                         "\xEF\xBC\xB8", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER X */
+                         "\xEF\xBD\x98", /* Shift JIS FULLWIDTH LATIN SMALL LETTER X */
+                         "\xEF\xBC\xB0", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER P */
+                         "\xEF\xBD\x90", /* Shift JIS FULLWIDTH LATIN SMALL LETTER P */
+                         "\xEF\xBC\xB2", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER R */
+                         "\xEF\xBD\x92", /* Shift JIS FULLWIDTH LATIN SMALL LETTER R */
+                         "\xEF\xBC\xB3", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER S */
+                         "\xEF\xBD\x93", /* Shift JIS FULLWIDTH LATIN SMALL LETTER S */
+                         "\xEF\xBC\xA9", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER I */
+                         "\xEF\xBD\x89", /* Shift JIS FULLWIDTH LATIN SMALL LETTER I */
+                         "\xEF\xBC\xAF", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER O */
+                         "\xEF\xBD\x8F", /* Shift JIS FULLWIDTH LATIN SMALL LETTER O */
+                         "\xEF\xBC\xAE", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER N */
+                         "\xEF\xBD\x8E", /* Shift JIS FULLWIDTH LATIN SMALL LETTER N */
+                         "\xEF\xBC\xAC", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER L */
+                         "\xEF\xBD\x8C", /* Shift JIS FULLWIDTH LATIN SMALL LETTER L */
+                         "\xEF\xBC\xB5", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER U */
+                         "\xEF\xBD\x95", /* Shift JIS FULLWIDTH LATIN SMALL LETTER U */
+                         "\xE2\x81\xBF", /* Shift JIS FULLWIDTH SUPERSCRIPT N */
+                         "\xCA\x9F", /* L UNICODE IPA Extension */
+                         "\xCA\x80", /* R UNICODE IPA Extension */
+                         "\xC9\xB4"),  /* N UNICODE IPA Extension */
+                   array('l', 'l', 'r', 'r', 'n', 'n', 'E', 'E', 'e', 'e', 'X', 'X', 'x', 'x',
+                         'P', 'P', 'p', 'p', 'R', 'R', 'r', 'r', 'S', 'S', 's', 's', 'I', 'I',
+                         'i', 'i', 'O', 'O', 'o', 'o', 'N', 'N', 'n', 'n', 'L', 'L', 'l', 'l',
+                         'U', 'U', 'u', 'u', 'n', 'n', 'E', 'e', 'X', 'x', 'P', 'p', 'R', 'r',
+                         'S', 's', 'I', 'i', 'O', 'o', 'N', 'n', 'L', 'l', 'U', 'u', 'n', 'l', 'r', 'n'));
+  if ((count($tags)>3) && (count($tags[3])>0))
+    foreach ($tags[3] as $nr=>$value)
+    {
+    /* Remove comments */
+    $newvalue = preg_replace('/(\/\*.*\*\/)/','$2',$value);
+    /* Translate dangerous characters */
+    $newvalue = str_replace($replace[0], $replace[1], $newvalue);
+    sq_defang($newvalue);
+    /* Rename dangerous CSS */
+    $newvalue = preg_replace('/expression/i', 'idiocy', $newvalue);
+    $newvalue = preg_replace('/url/i', 'idiocy', $newvalue);
+    $newattrs = preg_replace('/'.preg_quote($value, '/').'$/', $newvalue, $tags[1][$nr]);
+    $newtag = preg_replace('/'.preg_quote($tags[1][$nr], '/').'/', $newattrs, $tags[0][$nr]);
+    $html = preg_replace('/'.preg_quote($tags[0][$nr], '/').'/', $newtag, $html);
+    }
+
+  return $html;
+  }
+
 
 function rcmail_print_body($part, $safe=FALSE, $plain=FALSE)
   {
@@ -533,7 +651,7 @@
       $body = preg_replace($remote_patterns, $remote_replaces, $body);
       }
 
-    return Q($body, 'show', FALSE);
+    return Q(rcmail_html_filter($body), 'show', FALSE);
     }
 
   // text/enriched
There  is still some  unsanitized strings  but IE  does not  trigger any
alert any more. We will use  this patch as a temporary fix for Roundcube
Debian package unless you see a better way to handle this issue.
-- 
Treat end of file conditions in a uniform manner.
            - The Elements of Programming Style (Kernighan & Plauger)

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