Citrix Application Delivery Controller (ADC) formerly known as NetScaler ADC and Citrix Gateway 10.5, 11.1, 12.0, 12.1, and 13.0 formerly known as NetScaler Gateway have been found to have a vulnerability that, if exploited, might allow Directory Traversal.
In order to patch this vulnerability, please install the official patch Citrix made available for supported, vulnerable instances.