Ubuntu Security Notice 990-1 – Marsh Ray and Steve Dispensa discovered a flaw in the TLS and SSLv3 protocols. If an attacker could perform a man in the middle attack at the start of a TLS connection, the attacker could inject arbitrary content at the beginning of the user’s session. This update adds backported support for the new RFC5746 renegotiation extension and will use it when both the client and the server support it.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/94087/USN-990-1.txt
Source: https://packetstormsecurity.com/files/94087/Ubuntu-Security-Notice-990-1.html