  Discovering the malicious or vulnerable anchor node is an essential problem
in wireless sensor networks (WSNs). In wireless sensor networks, anchor nodes
are the nodes that know its current location. Neighbouring nodes or non-anchor
nodes calculate its location coordinate (or location reference) with the help
of anchor nodes. Ingenuous localization is not possible in the presence of a
cheating anchor node or a cheating node. Nowadays, its a challenging task to
identify the cheating anchor node or cheating node in a network. Even after
finding out the location of the cheating anchor node, there is no assurance,
that the identified node is legitimate or not. This paper aims to localize the
cheating anchor nodes using trilateration algorithm and later associate it with
Mahalanobis distance to obtain maximum accuracy in detecting malicious or
cheating anchor nodes during localization. We were able to attain a
considerable reduction in the error achieved during localization. For
implementation purpose, we simulated our scheme using ns3 network simulator.
