Bro 2.6.4 release (security update)

A security patch release, Bro v2.6.4, is now available for
download:

  https://www.zeek.org/downloads/bro-2.6.4.tar.gz
  https://www.zeek.org/downloads/bro-2.6.4.tar.gz.asc

Bro v2.6.4 addresses a potential Denial of Service
vulnerability:

* The NTLM analyzer did not properly handle AV Pair sequences
  that were either empty or unterminated, resulting in invalid
  memory access or heap buffer over-read. The NTLM analyzer
  is enabled by default and used in the analysis of SMB,
  DCE/RPC, and GSSAPI protocols.

  Thanks to Chris Hinshaw for reporting the issue.