The remote host is missing an update to the system as announced in the referenced advisory FreeBSD-SA-06:19.openssl.asc
Upgrade your system to the appropriate stable release or security branch dated after the correction date https://secure1.securityspace.com/smysecure/catid.html?in=FreeBSD-SA-06:19.openssl.asc
FreeBSD includes software from the OpenSSL Project. The OpenSSL Project is a collaborative effort to develop a robust, commercial-grade, full-featured, and Open Source toolkit implementing the Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1) protocols as well as a full-strength general purpose cryptography library. PKCS#1 v1.5 is a standard for padding data before performing a cryptographic operation using the RSA algorithm. PKCS#1 v1.5 signatures are for example used in X.509 certificates. RSA public keys may use a variety of public exponents, of which 3, 17, and 65537 are most common. As a result of a number of known attacks, most keys generated recently use a public exponent of at least 65537. When verifying a PKCS#1 v1.5 signature, OpenSSL ignores any bytes which follow the cryptographic hash being signed. In a valid signature there will be no such bytes.