The jsondecode function in plugins/contextreactionblock.inc in the Context module 6.x-2.x before 6.x-3.2 and 7.x-3.x before 7.x-3.0 for Drupal, when using a version of PHP that does not support the jsondecode function, allows remote attackers to execute arbitrary PHP code via unspecified vectors related to Ajax operations, possibly involving eval injection.

The Context module 6.x-3.x before 6.x-3.1 and 7.x-3.x before 7.x-3.0-beta6 for Drupal does not properly restrict access to block content, which allows remote attackers to obtain sensitive information via a crafted request.

The json rendering functionality in the Context module 6.x-2.x before 6.x-3.2 and 7.x-3.x before 7.x-3.0 for Drupal uses Drupal's token scheme to restrict access to blocks, which makes it easier for remote authenticated users to guess the access token for a block by leveraging the token from a block to which the user has access.