Red Hat Security Advisory 2015-0800-01 – OpenSSL is a toolkit that implements the Secure Sockets Layer and Transport Layer Security protocols, as well as a full-strength, general purpose cryptography library. It was discovered that OpenSSL would accept ephemeral RSA keys when using non-export RSA cipher suites. A malicious server could make a TLS/SSL client using OpenSSL use a weaker key exchange method. An integer underflow flaw, leading to a buffer overflow, was found in the way OpenSSL decoded malformed Base64-encoded inputs. An attacker able to make an application using OpenSSL decode a specially crafted Base64-encoded input could use this flaw to cause the application to crash. Note: this flaw is not exploitable via the TLS/SSL protocol because the data being transferred is not Base64-encoded.