nss - security update

Several vulnerabilities have been discovered in nss, the Mozilla Network
Security Service library. The Common Vulnerabilities and Exposures project
identifies the following problems:

• CVE-2015-2721
  Karthikeyan Bhargavan discovered that NSS incorrectly handles state
  transitions for the TLS state machine. A man-in-the-middle attacker
  could exploit this flaw to skip the ServerKeyExchange message and
  remove the forward-secrecy property.
• CVE-2015-2730
  Watson Ladd discovered that NSS does not properly perform Elliptical
  Curve Cryptography (ECC) multiplication, allowing a remote attacker
  to potentially spoof ECDSA signatures.

For the oldstable distribution (wheezy), these problems have been fixed
in version 2:3.14.5-1+deb7u5.

For the stable distribution (jessie), these problems have been fixed in
version 2:3.17.2-1.1+deb8u1.

For the testing distribution (stretch), these problems have been fixed
in version 2:3.19.1-1.

For the unstable distribution (sid), these problems have been fixed in
version 2:3.19.1-1.

We recommend that you upgrade your nss packages.