Openswan 2.6.39 and earlier allows remote attackers to cause a denial of service (NULL pointer dereference and IKE daemon restart) via IKEv2 packets that lack expected payloads.

The pluto IKE daemon in Openswan and Strongswan IPsec 2.6 before 2.6.21 and 2.4 before 2.4.14, and Strongswan 4.2 before 4.2.14 and 2.8 before 2.8.9, allows remote attackers to cause a denial of service (daemon crash and restart) via a crafted (1) RUTHERE or (2) RUTHEREACK Dead Peer Detection (DPD) IPsec IKE Notification message that triggers a NULL pointer dereference related to inconsistent ISAKMP state and the lack of a phase2 state association in DPD.