OpenSSL is a toolkit that implements the Secure Sockets Layer , Transport Layer Security , and Datagram Transport Layer Security protocols, as well as a full-strength, general purpose cryptography library. A race condition was found in the way OpenSSL handled ServerHello messages with an included Supported EC Point Format extension. A malicious server could possibly use this flaw to cause a multi-threaded TLS/SSL client using OpenSSL to write into freed memory, causing the client to crash or execute arbitrary code. It was discovered that the OBJ_obj2txt function could fail to properly NUL-terminate its output. This could possibly cause an application using OpenSSL functions to format fields of X.509 certificates to disclose portions of its memory. A flaw was found in the way OpenSSL handled fragmented handshake packets. A man-in-the-middle attacker could use this flaw to force a TLS/SSL server using OpenSSL to use TLS 1.0, even if both the client and the server supported newer protocol versions. Multiple flaws were discovered in the way OpenSSL handled DTLS packets. A remote attacker could use these flaws to cause a DTLS server or client using OpenSSL to crash or use excessive amounts of memory. A NULL pointer dereference flaw was found in the way OpenSSL performed a handshake when using the anonymous Diffie-Hellman key exchange. A malicious server could cause a DTLS client using OpenSSL to crash if that client had anonymous DH cipher suites enabled. All OpenSSL users are advised to upgrade to these updated packages, which contain backported patches to correct these issues. For the update to take effect, all services linked to the OpenSSL library must be restarted or the system rebooted.