IKEv2 in strongSwan 4.0.7 before 5.1.3 allows remote attackers to bypass authentication by rekeying an IKESA during (1) initiation or (2) re-authentication, which triggers the IKESA state to be set to established.
The IKE daemon in strongSwan 4.3.x before 4.3.7 and 4.4.x before 4.4.1 does not properly check the return values of snprintf calls, which allows remote attackers to execute arbitrary code via crafted (1) certificate or (2) identity data that triggers buffer overflows.
charon/sa/ikesa.c in the charon daemon in strongSWAN before 4.3.1 allows remote attackers to cause a denial of service (NULL pointer dereference and crash) via an invalid IKESAINIT request that triggers "an incomplete state," followed by a CREATECHILDSA request.