Apache 2.2.x < 2.2.32 Multiple Vulnerabilities (httpoxy)

Medium Nessus Plugin ID 96450


The remote web server is affected by multiple vulnerabilities.


According to its banner, the version of Apache running on the remote host is 2.2.x prior to 2.2.32. It is, therefore, affected by the following vulnerabilities :

- The Apache HTTP Server is affected by a man-in-the-middle vulnerability known as 'httpoxy' due to a failure to properly resolve namespace conflicts in accordance with RFC 3875 section 4.1.18. The HTTP_PROXY environment variable is set based on untrusted user data in the 'Proxy' header of HTTP requests. The HTTP_PROXY environment variable is used by some web client libraries to specify a remote proxy server. An unauthenticated, remote attacker can exploit this, via a crafted 'Proxy' header in an HTTP request, to redirect an application's internal HTTP traffic to an arbitrary proxy server where it may be observed or manipulated.

- A flaw exists due to improper handling of whitespace patterns in user-agent headers. An unauthenticated, remote attacker can exploit this, via a specially crafted user-agent header, to cause the program to incorrectly process sequences of requests, resulting in interpreting responses incorrectly, polluting the cache, or disclosing the content from one request to a second downstream user-agent. (CVE-2016-8743)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.


Upgrade to Apache version 2.2.32 or later.

Note that the 'httpoxy' vulnerability can be mitigated by applying the workarounds or patches as referenced in the vendor advisory asf-httpoxy-response.txt.

See Also






Plugin Details

Severity: Medium

ID: 96450

File Name: apache_2_2_32.nasl

Version: $Revision: 1.5 $

Type: remote

Family: Web Servers

Published: 2017/01/12

Modified: 2018/01/22

Dependencies: 48204

Risk Information

Risk Factor: Medium


Base Score: 5.1

Temporal Score: 4.2

Vector: CVSS2#AV:N/AC:H/Au:N/C:P/I:P/A:P

Temporal Vector: CVSS2#E:F/RL:OF/RC:ND


Base Score: 8.1

Temporal Score: 7.4

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:F/RL:O/RC:X

Vulnerability Information

CPE: cpe:/a:apache:http_server

Required KB Items: installed_sw/Apache, Settings/ParanoidReport

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 2017/01/13

Vulnerability Publication Date: 2016/07/18

Reference Information

CVE: CVE-2016-5387, CVE-2016-8743

BID: 91816, 95077

OSVDB: 141669, 149054

CERT: 797896