RPL is a routing protocol for low-power and lossyconstrained node networks. A malicious node can manipulateheader options used by RPL to track DODAG inconsistencies,thereby causing denial of service attacks, increased controlmessage overhead, and black-holes at the targeted node. RPLcounteracts DODAG inconsistencies by using a fixed threshold,upon reaching which all subsequent packets with erroneousheader options are ignored. However, the fixed threshold isarbitrary and does not resolve the black-hole issue either. Toaddress this we present a mitigation strategy that allows nodesto dynamically adapt against a DODAG inconsistency attack. Wealso present the forced black-hole attack problem and presenta solution that can be used to mitigate it. Results from ourexperiments show that our proposed approach mitigates theseattacks without any significant overhead.