A vulnerability in the TLS protocol would allow a man-in-the-middle attacker to downgrade vulnerable TLS connections using ephemeral Diffie-Hellman key exchange to 512-bit export-grade cryptography. This vulnerability is also known as Logjam [CVE-2015-4000].
When processing an ECParameters structure OpenSSL enters an infinite loop if the curve specified is over a specially malformed binary polynomial field. [CVE-2015-1788]
X509_cmp_time does not properly check the length of the ASN1_TIME string and can read a few bytes out of bounds. In addition, X509_cmp_time accepts an arbitrary number of fractional seconds in the time string. [CVE-2015-1789]
The PKCS#7 parsing code does not handle missing inner EncryptedContent correctly. [CVE-2015-1790]
When verifying a signedData message the CMS code can enter an infinite loop if presented with an unknown hash function OID. [CVE-2015-1792]
If a NewSessionTicket is received by a multi-threaded client when attempting to reuse a previous ticket then a race condition can occur, potentially leading to a double free of the ticket data. [CVE-2015-1791]
The OpenSSL advisory also describes a problem that is identified as CVE-2014-8176, which is already fixed by an earlier FreeBSD Errata Notice, FreeBSD-EN-15:02.openssl.
