title: Strange ValidateInputIfRequiredByConfig error
body: <p>I'm getting random exception caused by ValidateInputIfRequiredByConfig().</p>
  
  <p>I don't have exact message, since our server is pt-BR, so error message is translated.</p>
  
  <p>I know that this error can be thrown if user puts malicious code in input, ie example. But it's not case here.</p>
  
  <p>I'm getting this one, requesting some images. Below some info from elmah.</p>
  
  <pre><code>HTTP_USER_AGENT:    GbPlugin
  PATH_INFO:          /Content/images/BannerWelcome.jpg?1110311762734
  PATH_TRANSLATED:    C:\inetpub\wwwroot\Content\images\BannerWelcome.jpg?1110311762734
  REQUEST_METHOD:     GET
  SCRIPT_NAME:        /Content/images/BannerWelcome.jpg?1110311762734
  </code></pre>
  
  <p>Application is ASP.NET MVC 3, running on Windows 2008, IIS 7.5</p>
  
  <p><strong>EDIT:</strong></p>
  
  <p>Exception message in pt-BR:</p>
  
  <pre><code>System.Web.HttpException
  Um valor possivelmente perigoso Request.Path foi detectado no cliente (?).
  
  System.Web.HttpException (0x80004005): Um valor possivelmente perigoso Request.Path foi detectado no cliente (?).
     em System.Web.HttpRequest.ValidateInputIfRequiredByConfig()
     em System.Web.HttpApplication.PipelineStepManager.ValidateHelper(HttpContext context)
  </code></pre>
  
  <p><strong>EDIT:</strong></p>
  
  <p>Exception message in English: "A potentially dangerous value was detected from the client Request.Path"</p>
  
  <p><strong>EDIT 2:</strong></p>
  
  <p>I can't reproduce this error. As I know it is just in request to this image.</p>