Drupal 7.34 and Drupal 6.34, maintenance releases which contain fixes for security vulnerabilities, are now available for download. See the Drupal 7.34 and Drupal 6.34 release notes for further information.
Drupal 7.34 and 6.34 were released in response to the discovery of security vulnerabilities. Details can be found in the official security advisory: SA-CORE-2014-006
To fix the security problem, please upgrade to either Drupal 7.34 or Drupal 6.34.