|Description||Mozilla Network Security Services (NSS) before 3.19, as used in Mozilla Firefox before 39.0, Firefox ESR 31.x before 31.8 and 38.x before 38.1, Thunderbird before 38.1, and other products, does not properly determine state transitions for the TLS state machine, which allows man-in-the-middle attackers to defeat cryptographic protection mechanisms by blocking messages, as demonstrated by removing a forward-secrecy property by blocking a ServerKeyExchange message, aka a "SMACK SKIP-TLS" issue.|
|Source||CVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub code/issues, web search, more)|
|References||DLA-315-1, DSA-3300-1, DSA-3324-1, DSA-3336-1|
|NVD severity||medium (attack range: remote)|
Vulnerable and fixed packages
The table below lists information on source packages.
|nss (PTS)||jessie (security), jessie||2:3.26-1+debu8u3||fixed|
|stretch (security), stretch||2:3.26.2-1.1+deb9u1||fixed|
The information below is based on the following data on fixed versions.
NSS patch: https://hg.mozilla.org/projects/nss/rev/6b4770c76bc8
NSS testcase: https://hg.mozilla.org/projects/nss/rev/1865635f5df5