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.