NSS 3.55 release notes


The NSS team has released Network Security Services (NSS) 3.55 on 24 July 2020, which is a minor release.

The NSS team would like to recognize first-time contributors:

  • Danh

Distribution Information

The HG tag is NSS_3_55_RTM. NSS 3.55 requires NSPR 4.27 or newer.

NSS 3.55 source distributions are available on ftp.mozilla.org for secure HTTPS download:

Other releases are available Release notes for recent versions of NSS.

Notable Changes in NSS 3.55

  • P384 and P521 elliptic curve implementations are replaced with verifiable implementations from Fiat-Crypto and ECCKiila. Special thanks to the Network and Information Security Group (NISEC) at Tampere University.

  • PK11_FindCertInSlot is added. With this function, a given slot can be queried with a DER-Encoded certificate, providing performance and usability improvements over other mechanisms. See Bug 1649633 for more details.

  • DTLS 1.3 implementation is updated to draft-38. See Bug 1647752 for details.

  • NSPR dependency updated to 4.27.

Known Issues

  • On some platforms, using the Makefile builds fails to locate seccomon.h; ensure you are using make all rather than just make. Another potential workaround is to use the gyp-based build.sh script. If this affects you, please help us narrow down the cause in Bug 1653975.

Bugs fixed in NSS 3.55

  • Bug 1631583 (CVE-2020-6829, CVE-2020-12400) - Replace P384 and P521 with new, verifiable implementations from Fiat-Crypto and ECCKiila.

  • Bug 1649487 - Move overzealous assertion in VFY_EndWithSignature.

  • Bug 1631573 (CVE-2020-12401) - Remove unnecessary scalar padding.

  • Bug 1636771 (CVE-2020-12403) - Explicitly disable multi-part ChaCha20 (which was not functioning correctly) and more strictly enforce tag length.

  • Bug 1649648 - Don’t memcpy zero bytes (sanitizer fix).

  • Bug 1649316 - Don’t memcpy zero bytes (sanitizer fix).

  • Bug 1649322 - Don’t memcpy zero bytes (sanitizer fix).

  • Bug 1653202 - Fix initialization bug in blapitest when compiled with NSS_DISABLE_DEPRECATED_SEED.

  • Bug 1646594 - Fix AVX2 detection in makefile builds.

  • Bug 1649633 - Add PK11_FindCertInSlot to search a given slot for a DER-encoded certificate.

  • Bug 1651520 - Fix slotLock race in NSC_GetTokenInfo.

  • Bug 1647752 - Update DTLS 1.3 implementation to draft-38.

  • Bug 1649190 - Run cipher, sdr, and ocsp tests under standard test cycle in CI.

  • Bug 1649226 - Add Wycheproof ECDSA tests.

  • Bug 1637222 - Consistently enforce IV requirements for DES and 3DES.

  • Bug 1067214 - Enforce minimum PKCS#1 v1.5 padding length in RSA_CheckSignRecover.

  • Bug 1643528 - Fix compilation error with -Werror=strict-prototypes.

  • Bug 1646324 - Advertise PKCS#1 schemes for certificates in the signature_algorithms extension.

  • Bug 1652331 - Update NSS 3.55 NSPR version to 4.27.

This Bugzilla query returns all the bugs fixed in NSS 3.55:



NSS 3.55 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 3.55 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).