strongSwan -- ECDSA signature verification issue

strongSwan security team reports:

If the openssl plugin is used for ECDSA signature verification an empty,
zeroed or otherwise invalid signature is handled as a legitimate one.
Both IKEv1 and IKEv2 are affected.
Affected are only installations that have enabled and loaded the OpenSSL
crypto backend (–enable-openssl). Builds using the default crypto backends
are not affected.