Difference between revisions of "CRV2 RevCodePersistentAntiPatternPHP"

Revision as of 19:37, 3 May 2014

It is pretty easy to remove all persistent XSS attacks from PHP, just remove all instances of output functions (such as echo and print) with their safe counterparts from OWASP PHP Security Core Library, and then whenever you need HTML elements to be outputted, used the appropriate functions or PHP tags. There's a scanner in PHP Security Project that scans for this and can replace it effectively as well.

Scanner PHP

As mentioned earlier, you can download the Scanner PHP using the PHPSERC framework at https://www.owasp.org/index.php/OWASP_PHP_Security_Project

 /**
 * Array to hold all the words that are considered unsafe.
 * @var Array
 */
 public static $blacklist = array("T_ECHO"=>"echo", "T_PRINT"=>"print","printf","vprintf");

 /**
 * Function to start a scan in a directory.
 * @return Array
 * @throws DirectoryNotFoundException
 */
 public static function scanDir($parentDirectory)
 {
  $occurences = array(array());

 //if the directory/file does not exists, then throw and error.
   if ( !file_exists( $parentDirectory ) )

{ throw new DirectoryORFileNotFoundException("ERROR: Directory not found!"); }

//get the list of all the files inside this directory. $allFiles = new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($parentDirectory));

$fileList = array();

//remove (.), (..) and directories from the list of all files so that only files are left. while($allFiles->valid()) { if (!$allFiles->isDot()) //remove present director[.] and parent directory[..] { if (!is_dir($allFiles->key())) { array_push($fileList, $allFiles->key()); } }

$allFiles->next(); }

$i = 0; foreach ($fileList as $file) //add errors found to the results. { if (pathinfo($file, PATHINFO_EXTENSION)!="php") continue; $occurences[$i]['file'] = realpath($file); $occurences[$i]['result'] = Scanner::scanFile($file);

$i++; }

return $occurences; }