title: Non printable regex
body: <p>I am in need of a regex that will match non printable characters. The reason being is that I have a hailstorm spammer that is abusing my network and is getting past my PCRE based heuristic filter by obfuscating his subjects with non printable characters. Therefore, any text based rules I create are bypassed because there is no match. </p>
  
  <p>For example: </p>
  
  <p>The regular text based subject: <strong>Reduce tech cоsts with clоud cоmputing</strong></p>
  
  <p>The obfuscated subject: </p>
  
  <ul>
  <li>Reduce tech cÐ¾sts with clÐ¾ud cÐ¾mputing</li>
  <li>ReduÑe teÑh cÐ¾sts with ÑlÐ¾ud ÑÐ¾mputing</li>
  <li>ReduÑe teÑh Ñosts with Ñloud Ñomputing</li>
  <li>RÐµducÐµ tÐµch cÐ¾sts with ÑlÐ¾ud ÑÐ¾mputing</li>
  </ul>
  
  <p>What I am looking for is a regex that I can modify to match all of the phrases that have been used and build a list of regexes.</p>
  
  <p>Maybe, if I can get a regex that will match the subjects, I can meta them together with other matching header information that will thwart these messages. </p>
  
  <p>Any help would be much appreciated. </p>