[security] Go 1.6.3 and 1.7rc2 are released

[Chris Broadfoot]

A security-related issue was recently reported in Go's net/http/cgi package and net/http package when used in a CGI environment. Go 1.6.3 and Go 1.7rc2 will contain a fix for this issue.

Go versions 1.0-1.6.2 and 1.7rc1 are vulnerable to an input validation flaw in the CGI components resulting in the HTTP_PROXY environment variable being set by the incoming Proxy header. This environment variable was also used to set the outgoing proxy, enabling an attacker to insert a proxy into outgoing requests of a CGI program.
This is CVE-2016-5386 and was addressed by this change: https://golang.org/cl/25010, tracked in this issue: https://golang.org/issue/16405

The Go team would like to thank Dominic Scheirlinck for coordinating disclosure of this issue across multiple languages and CGI environments. Read more about "httpoxy" here: https://httpoxy.org/

Go 1.6.3 also adds support for macOS Sierra. See https://golang.org/issue/16354 for details.

Downloads are available at https://golang.org/dl for all supported platforms.

Cheers,
Chris (on behalf of the Go team)