Presented herein are techniques to reduce the vulnerabilities of network elements to malicious API calls. One or more filters that validate data across an API boundary at a network element are dynamically loaded into the network element such that a reboot of the network element is not required to use the one or more filters. An API call is received for an API function, wherein the API call contains one or more parameter values associated with the API function. The parameters may be validated using the one or more filters. If it is determined that the one or more filters validate the parameters for the API function, the API function may be executed using the parameter values. If it is determined that the one or more filters do not validate the parameters for the API function, the execution of the API function may be aborted.