The OG access fields (visibility fields) implementation in Organic Groups (OG) module 7.x-2.x before 7.x-2.3 for Drupal does not properly restrict access to private groups, which allows remote authenticated users to guess node IDs, subscribe to, and read the content of arbitrary private groups via unspecified vectors.

The Organic Groups (OG) module 7.x-2.x before 7.x-2.3 for Drupal allows remote authenticated users to bypass group restrictions on nodes with all groups set to optional input via an empty group field.

The Organic Groups (OG) module 7.x-2.x before 7.x-2.3 for Drupal allows remote attackers to bypass access restrictions and post to arbitrary groups via a group audience field, as demonstrated by the og_group_ref field.

The Organic Groups (OG) module 7.x-1.x before 7.x-1.5 for Drupal does not properly maintain pending group memberships, which allows remote authenticated users to post to arbitrary groups by modifying their own account while a pending membership is waiting to be approved.

The Organic Groups (OG) module 5.x before 5.x-7.3 and 6.x before 6.x-1.0-RC1, a module for Drupal, allows remote attackers to obtain sensitive information (private group names) via unspecified vectors.