Varnish 3.x before 3.0.7, when used in certain stacked installations, allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via a header line terminated by a \r (carriage return) character in conjunction with multiple Content-Length headers in an HTTP request.
lists.opensuse.org/opensuse-updates/2016-05/msg00064.html
www.debian.org/security/2016/dsa-3553
www.openwall.com/lists/oss-security/2016/04/16/1
www.openwall.com/lists/oss-security/2016/04/18/7
github.com/varnish/Varnish-Cache/commit/29870c8fe95e4e8a672f6f28c5fbe692bea09e9c
github.com/varnish/Varnish-Cache/commit/85e8468bec9416bd7e16b0d80cb820ecd2b330c3
security.gentoo.org/glsa/201607-10
www.varnish-cache.org/lists/pipermail/varnish-announce/2015-March/000701.html