NSS release notes


Network Security Services (NSS) is a patch release for NSS 3.16. The bug fixes in NSS are described in the "Bugs Fixed" section below.

Distribution Information

The HG tag is NSS_3_16_2_3_RTM. NSS requires NSPR 4.10.6 or newer.

NSS source distributions are available on ftp.mozilla.org for secure HTTPS download:

New in NSS

This patch release fixes a bug and contains a backport of the TLS_FALLBACK_SCSV feature, which was originally made available in NSS 3.17.1.

New Functionality

  • TLS_FALLBACK_SCSV is a signaling cipher suite value that indicates a handshake is the result of TLS version fallback.

New Macros

  • in ssl.h
    • SSL_ENABLE_FALLBACK_SCSV - an SSL socket option that enables TLS_FALLBACK_SCSV. Off by default.
  • in sslerr.h
  • in sslproto.h
    • TLS_FALLBACK_SCSV - a a signaling cipher suite value that indicates a handshake is the result of TLS version fallback.

Notable Changes in NSS

  • Bug 1057161: Check that an imported elliptic curve public key is valid. Previously NSS would only validate the peer's public key before performing ECDH key agreement. Now EC public keys are validated at import time.

Bugs fixed in NSS

  • Bug 1057161 - NSS hangs with 100% CPU on invalid EC key
  • Bug 1036735 - Add support for draft-ietf-tls-downgrade-scsv to NSS


NSS shared libraries are backward compatible with all older NSS 3.x shared libraries. A program linked with older NSS 3.x shared libraries will work with NSS shared libraries without recompiling or relinking. Furthermore, applications that restrict their use of NSS APIs to the functions listed in NSS Public Functions will remain compatible with future versions of the NSS shared libraries.


Bugs discovered should be reported by filing a bug report with bugzilla.mozilla.org (product NSS).


Document Tags and Contributors

Contributors to this page: kscarfone, kaie
Last updated by: kscarfone,