CVE-2016-4694

Severity: critical (CVSS 9.1 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2016-09-25 · updated 2026-06-17
Weakness: CWE-284

Description

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.

Affected products

macOS: through 10.11.6
Apple Os X Server: through 5.1

References

http://lists.apple.com/archives/security-announce/2016/Sep/msg00006.html
http://lists.apple.com/archives/security-announce/2016/Sep/msg00009.html
http://www.securityfocus.com/bid/93060
http://www.securitytracker.com/id/1036853
https://support.apple.com/HT207170
https://support.apple.com/HT207171
http://lists.apple.com/archives/security-announce/2016/Sep/msg00006.html
http://lists.apple.com/archives/security-announce/2016/Sep/msg00009.html
http://www.securityfocus.com/bid/93060
http://www.securitytracker.com/id/1036853
https://support.apple.com/HT207170
https://support.apple.com/HT207171

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