varnish:6 security update

Varnish Cache is a high-performance HTTP accelerator. It stores web pages in memory so web servers don't have to create the same web page over and over again, giving the website a significant speed up.

Security Fix(es):

* varnish: HTTP/2 request smuggling attack via a large Content-Length header for a POST request (CVE-2021-36740)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

CVE-2021-36740
Varnish Cache, with HTTP/2 enabled, allows request smuggling and VCL authorization bypass via a large Content-Length header for a POST request. This affects Varnish Enterprise 6.0.x before 6.0.8r3, and Varnish Cache 5.x and 6.x before 6.5.2, 6.6.x before 6.6.1, and 6.0 LTS before 6.0.8.

Modularity name: varnish
Stream name: 6