Acquia Drupal 1.2.64 (Drupal 6.34 core from Pressflow) contains the following updates:

Security updates
* Updated Drupal core to 6.34 (https://www.drupal.org/drupal-6.34-release-notes). This also fixes a session hikacking security issue described in SA-CORE-2014-006 (https://www.drupal.org/SA-CORE-2014-006).
* Updated the Secure Password Hashes module to 6.x-2.1 (https://www.drupal.org/node/2378375). This also fixes a denial of service security issue described in SA-CONTRIB-2014-113 (https://www.drupal.org/node/2378367).

Other updates
* none