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) R_U_THERE or (2) R_U_THERE_ACK 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.
strongSwan 4.2.6 and earlier allows remote attackers to cause a denial of service (daemon crash) via an IKE_SA_INIT message with a large number of NULL values in a Key Exchange payload, which triggers a NULL pointer dereference for the return value of the mpz_export function in the GNU Multiprecision Library (GMP).