CVE-2014-9721
libzmq before 4.0.6 and 4.1.x before 4.1.1 allows remote attackers to conduct downgrade attacks and bypass ZMTP v3 protocol security mechanisms via a ZMTP v2 or earlier header.
Date published : 2015-06-03
https://github.com/zeromq/libzmq/issues/1273
https://github.com/zeromq/zeromq4-x/commit/b6e3e0f601e2c1ec1f3aac880ed6a3fe63043e51