Content Centric Networking (CCN) [1] is a new network paradigm designed to satisfy user needs considering the growth of data demand. Named Data Networking (NDN) [2] is a research project that is developing the future Internet architecture using the principles behind CCN. In this novel architecture, the contents are addressed by their name and not by their location. Thus, the attention is shifted from user to content, resulting in a caching network that is more efficient and flexible than an IP network for content distribution and management with beneficial effects on timely delivery. In NDN, the content objects are divided into chunks, each digitally signed by its producer, and most papers assume that verification is made only by the content consumer. In order to perform signature verification, a node needs the signer’s key, which can be easily retrieved by issuing a standard interest message. Although content verification at the end node prevents disruptive attacks in which false data is delivered to applications, the verification of key validity is also necessary. Otherwise, false data would be cached and forwarded instead of correct data resulting in a denial of service and paving the way for more sophisticated attacks.