Buffer overflow in the atodn function in strongSwan 2.0.0 through 4.3.4, when Opportunistic Encryption is enabled and an RSA key is being used, allows remote attackers to cause a denial of service (pluto IKE daemon crash) and possibly execute arbitrary code via crafted DNS TXT records. NOTE: this might be the same vulnerability as CVE-2013-2053 and CVE-2013-2054.

charon/sa/ike_sa.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 IKE_SA_INIT request that triggers "an incomplete state," followed by a CREATE_CHILD_SA request.

charon/sa/tasks/child_create.c in the charon daemon in strongSWAN before 4.3.1 switches the NULL checks for TSi and TSr payloads, which allows remote attackers to cause a denial of service via an IKE_AUTH request without a (1) TSi or (2) TSr traffic selector.

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).