CVE-2016-4694 in macOS
Summary
The Apache HTTP Server in Apple OS X before 10.12 and OS X Server before 5.2 follows RFC 3875 section 4.1.18 and therefore does not protect applications from the presence of untrusted CGI client data in the HTTP_PROXY environment variable, which might allow remote attackers to redirect an application's outbound HTTP traffic to an arbitrary proxy server via a crafted Proxy header in an HTTP request, aka an "httpoxy" issue, a related issue to CVE-2016-5387.
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