The performance of Named Data Networking (NDN) depends on the caching efficiency of routers. Cache Pollution Attack (CPA) refers to colonization of unpopular contents in the Content Store (CS) of an NDN router, which leads to declined Quality of Service (QoS) in NDN. CPA has very few solutions proposed for its mitigation. Most of these solutions are based on the statistics of the router itself. However, an attacker can influence these statistics by requesting unpopular contents repeatedly. This article proposes a new parameter for the detection of CPA, which is based on the number of distinct users requesting interest packets for a content over a period of time. The local popularity of the attackers’ content does not affect the proposed approach. Results show that the proposed approach consumes less storage, reduces processing time, and more effectively mitigates the CPA, as compared to the other existing approaches.