The NASA’s Interplanetary Overlay Network (ION) is an implementation of Delay/Disruption Tolerant Networking (DTN). A vulnerability exists in the version ION-DTN BPv7 implementation version 4.1.3 when receiving a bundle with an improper reference to the imc scheme with valid Service-Specific Part (SSP) in their Previous Node Block. The vulnerability can cause ION to become unresponsive. This vulnerability is fixed in 4.1.3s.