Apache 2.4.x < 2.4.56 Multiple Vulnerabilities

critical Nessus Plugin ID 172186


The remote web server is affected by multiple vulnerabilities.


The version of Apache httpd installed on the remote host is prior to 2.4.56. It is, therefore, affected by multiple vulnerabilities as referenced in the 2.4.56 advisory.

- HTTP request splitting with mod_rewrite and mod_proxy: Some mod_proxy configurations on Apache HTTP Server versions 2.4.0 through 2.4.55 allow a HTTP Request Smuggling attack. Configurations are affected when mod_proxy is enabled along with some form of RewriteRule or ProxyPassMatch in which a non-specific pattern matches some portion of the user-supplied request-target (URL) data and is then re-inserted into the proxied request-target using variable substitution. For example, something like: RewriteEngine on RewriteRule ^/here/(.*) http://example.com:8080/elsewhere?$1 http://example.com:8080/elsewhere ; [P] ProxyPassReverse /here/ http://example.com:8080/ http://example.com:8080/ Request splitting/smuggling could result in bypass of access controls in the proxy server, proxying unintended URLs to existing origin servers, and cache poisoning. Acknowledgements: finder: Lars Krapf of Adobe (CVE-2023-25690)

- Apache HTTP Server: mod_proxy_uwsgi HTTP response splitting: HTTP Response Smuggling vulnerability in Apache HTTP Server via mod_proxy_uwsgi. This issue affects Apache HTTP Server: from 2.4.30 through 2.4.55.
Special characters in the origin response header can truncate/split the response forwarded to the client.
Acknowledgements: finder: Dimas Fariski Setyawan Putra (nyxsorcerer) (CVE-2023-27522)

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 2.4.56 or later.

Plugin Details

Severity: Critical

ID: 172186

File Name: apache_2_4_56.nasl

Version: 1.4

Type: combined

Agent: windows, macosx, unix

Family: Web Servers

Published: 3/7/2023

Updated: 9/14/2023

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent

Risk Information


Risk Factor: Critical

Score: 9.5


Risk Factor: Medium

Base Score: 6.4

Temporal Score: 5

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

CVSS Score Source: CVE-2023-25690


Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.8

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

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:apache:httpd, cpe:/a:apache:http_server

Required KB Items: installed_sw/Apache

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 3/7/2023

Vulnerability Publication Date: 1/29/2023

Reference Information

CVE: CVE-2023-25690, CVE-2023-27522

IAVA: 2023-A-0124