CVE-2016-1000109

Name: CVE-2016-1000109
Creator: NVD / NIST
Published: 2020-02-19T13:15:10.9+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.3/10EPSS 4.95%

Last modified Jun 17, 2026

CVE-2016-1000109 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. HHVM does not attempt to address RFC 3875 section 4.1.18 namespace conflicts and therefore does not protect CGI applications from the presence of untrusted client data in the HTTP_PROXY environment variable, which might allow remote attackers to redirect a CGI application's outbound HTTP traffic to an arbitrary proxy server via a crafted Proxy header in an HTTP request, aka an "httpoxy" issue. This issue affects HHVM versions prior to 3.9.6, all versions between 3.10.0 and 3.12.4 (inclusive), and all versions between 3.13.0 and 3.14.2 (inclusive).. EPSS estimates a 4.95% chance of exploitation in the next 30 days.

Description

HHVM does not attempt to address RFC 3875 section 4.1.18 namespace conflicts and therefore does not protect CGI applications from the presence of untrusted client data in the HTTP_PROXY environment variable, which might allow remote attackers to redirect a CGI application's outbound HTTP traffic to an arbitrary proxy server via a crafted Proxy header in an HTTP request, aka an "httpoxy" issue. This issue affects HHVM versions prior to 3.9.6, all versions between 3.10.0 and 3.12.4 (inclusive), and all versions between 3.13.0 and 3.14.2 (inclusive).

Metrics

CVSS 3.1

5.3/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

EPSS Probability

4.95%

91.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-665

Affected Software

Vendor	Product	Versions
Facebook	Hhvm	< 3.9.6
Facebook	Hhvm	>= 3.10.0, <= 3.12.4
Facebook	Hhvm	>= 3.13.0, <= 3.14.2

References

https://github.com/facebook/hhvm/commit/423b4b719afd5ef4e6e19d8447fbf7b6bc0d0a25Patch, Third Party Advisory
https://httpoxy.org/Exploit, Mitigation, Third Party Advisory
https://www.facebook.com/security/advisories/cve-2016-1000109Third Party Advisory
https://github.com/facebook/hhvm/commit/423b4b719afd5ef4e6e19d8447fbf7b6bc0d0a25Patch, Third Party Advisory
https://httpoxy.org/Exploit, Mitigation, Third Party Advisory
https://www.facebook.com/security/advisories/cve-2016-1000109Third Party Advisory

Timeline

Published: Feb 19, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2016-1000109?

How severe is CVE-2016-1000109?

CVE-2016-1000109 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 4.95% probability of exploitation in the next 30 days.

How do I fix CVE-2016-1000109?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2016-1000109?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST