USN-927-1 fixed vulnerabilities in NSS. Upstream NSS 3.12.6 added an additional checksum verification on libnssdbm3.so, but the Ubuntu packaging did not create this checksum. As a result, Firefox could not initialize the security component when the NSS Internal FIPS PKCS #11 Module was enabled. This update fixes the problem. We apologize for the inconvenience. Original advisory details: 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 support for the new new renegotiation extension and will use it when the server supports it.