libreswan: Invalid IKEv1 repeat IKE SA delete causes crash and restart

A NULL pointer dereference vulnerability was found in the Libreswan package. When an IKEv1 ISAKMP SA Informational Exchange packet contains a Delete/Notify payload followed by further Notifies that act on the ISAKMP SA, such as a duplicated Delete/Notify message, a NULL pointer dereference on the...