Changes with nginx 1.7.4                                         05 Aug 2014

    *) Security: pipelined commands were not discarded after STARTTLS
       command in SMTP proxy (CVE-2014-3556); the bug had appeared in 1.5.6.
       Thanks to Chris Boulton.

    *) Change: URI escaping now uses uppercase hexadecimal digits.
       Thanks to Piotr Sikora.

    *) Feature: now nginx can be build with BoringSSL and LibreSSL.
       Thanks to Piotr Sikora.

    *) Bugfix: requests might hang if resolver was used and a DNS server
       returned a malformed response; the bug had appeared in 1.5.8.

    *) Bugfix: in the ngx_http_spdy_module.
       Thanks to Piotr Sikora.

    *) Bugfix: the $uri variable might contain garbage when returning errors
       with code 400.
       Thanks to Sergey Bobrov.

    *) Bugfix: in error handling in the "proxy_store" directive and the
       ngx_http_dav_module.
       Thanks to Feng Gu.

    *) Bugfix: a segmentation fault might occur if logging of errors to
       syslog was used; the bug had appeared in 1.7.1.

    *) Bugfix: the $geoip_latitude, $geoip_longitude, $geoip_dma_code, and
       $geoip_area_code variables might not work.
       Thanks to Yichun Zhang.

    *) Bugfix: in memory allocation error handling.
       Thanks to Tatsuhiko Kubo and Piotr Sikora.
Changes with nginx 1.7.5                                         16 Sep 2014

    *) Security: it was possible to reuse SSL sessions in unrelated contexts
       if a shared SSL session cache or the same TLS session ticket key was
       used for multiple "server" blocks (CVE-2014-3616).
       Thanks to Antoine Delignat-Lavaud.

    *) Change: now the "stub_status" directive does not require a parameter.

    *) Feature: the "always" parameter of the "add_header" directive.

    *) Feature: the "proxy_next_upstream_tries",
       "proxy_next_upstream_timeout", "fastcgi_next_upstream_tries",
       "fastcgi_next_upstream_timeout", "memcached_next_upstream_tries",
       "memcached_next_upstream_timeout", "scgi_next_upstream_tries",
       "scgi_next_upstream_timeout", "uwsgi_next_upstream_tries", and
       "uwsgi_next_upstream_timeout" directives.

    *) Bugfix: in the "if" parameter of the "access_log" directive.

    *) Bugfix: in the ngx_http_perl_module.
       Thanks to Piotr Sikora.

    *) Bugfix: the "listen" directive of the mail proxy module did not allow
       to specify more than two parameters.

    *) Bugfix: the "sub_filter" directive did not work with a string to
       replace consisting of a single character.

    *) Bugfix: requests might hang if resolver was used and a timeout
       occurred during a DNS request.

    *) Bugfix: in the ngx_http_spdy_module when using with AIO.

    *) Bugfix: a segmentation fault might occur in a worker process if the
       "set" directive was used to change the "$http_...", "$sent_http_...",
       or "$upstream_http_..." variables.

    *) Bugfix: in memory allocation error handling.
       Thanks to Markus Linnala and Feng Gu.