Vulnerability · Published Mar 7, 2023 · Assigned by apache

CVE-2023-25690Apache HTTP Server: HTTP request splitting with mod_rewrite and mod_proxy

Critical 9.8

In plain English

A critical-severity security flaw in Apache HTTP Server from Apache Software Foundation. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 84.5% (higher than 99.7% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)9.8Critical
Exploit odds (30 days)84.5%top 0.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack tooling1Public PoC

Official description

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"; [P] ProxyPassReverse /here/ 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. Users are recommended to update to at least version 2.4.56 of Apache HTTP Server.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:8httpd2.4.37-51.module_el8.7.0+3515+9e4fe0d6.5ALSA-2023:1673
AlmaLinux:9httpd2.4.53-7.el9_1.5ALSA-2023:1670
AlmaLinux:9httpd-core2.4.53-7.el9_1.5ALSA-2023:1670
AlmaLinux:8httpd-devel2.4.37-51.module_el8.7.0+3515+9e4fe0d6.5ALSA-2023:1673
AlmaLinux:9httpd-devel2.4.53-7.el9_1.5ALSA-2023:1670
AlmaLinux:8httpd-filesystem2.4.37-51.module_el8.7.0+3515+9e4fe0d6.5ALSA-2023:1673
AlmaLinux:9httpd-filesystem2.4.53-7.el9_1.5ALSA-2023:1670
AlmaLinux:8httpd-manual2.4.37-51.module_el8.7.0+3515+9e4fe0d6.5ALSA-2023:1673
AlmaLinux:9httpd-manual2.4.53-7.el9_1.5ALSA-2023:1670
AlmaLinux:8httpd-tools2.4.37-51.module_el8.7.0+3515+9e4fe0d6.5ALSA-2023:1673
AlmaLinux:9httpd-tools2.4.53-7.el9_1.5ALSA-2023:1670
AlmaLinux:8mod_http21.15.7-5.module_el8.7.0+3515+9e4fe0d6.4ALSA-2023:1673
AlmaLinux:9mod_http21.15.19-3.el9_1.5ALSA-2023:1670
AlmaLinux:8mod_ldap2.4.37-51.module_el8.7.0+3515+9e4fe0d6.5ALSA-2023:1673
AlmaLinux:9mod_ldap2.4.53-7.el9_1.5ALSA-2023:1670
AlmaLinux:9mod_lua2.4.53-7.el9_1.5ALSA-2023:1670
AlmaLinux:8mod_md1:2.0.8-8.module_el8.6.0+2872+fe0ff7aaALSA-2023:1673
AlmaLinux:8mod_md1:2.0.8-8.module_el8.6.0+3031+fb177b09ALSA-2023:1673
AlmaLinux:8mod_proxy_html1:2.4.37-51.module_el8.7.0+3515+9e4fe0d6.5ALSA-2023:1673
AlmaLinux:9mod_proxy_html1:2.4.53-7.el9_1.5ALSA-2023:1670
AlmaLinux:8mod_session2.4.37-51.module_el8.7.0+3515+9e4fe0d6.5ALSA-2023:1673
AlmaLinux:9mod_session2.4.53-7.el9_1.5ALSA-2023:1670
AlmaLinux:8mod_ssl1:2.4.37-51.module_el8.7.0+3515+9e4fe0d6.5ALSA-2023:1673
AlmaLinux:9mod_ssl1:2.4.53-7.el9_1.5ALSA-2023:1670
Alpine:v3.20apache22.4.56-r0ALPINE-CVE-2023-25690
Alpine:v3.21apache22.4.56-r0ALPINE-CVE-2023-25690
Alpine:v3.22apache22.4.56-r0ALPINE-CVE-2023-25690
Alpine:v3.23apache22.4.56-r0ALPINE-CVE-2023-25690
Alpine:v3.24apache22.4.56-r0ALPINE-CVE-2023-25690
Debian:12apache22.4.56-1DEBIAN-CVE-2023-25690
Debian:13apache22.4.56-1DEBIAN-CVE-2023-25690
Debian:14apache22.4.56-1DEBIAN-CVE-2023-25690
Rocky Linux:8httpd0:2.4.37-51.module+el8.7.0+1059+126e9251RLSA-2023:1673
Rocky Linux:9httpd0:2.4.53-7.el9_1.5RLSA-2023:1670
Rocky Linux:8mod_http20:1.15.7-5.module+el8.6.0+823+f143cee1RLSA-2023:1673
Rocky Linux:9mod_http20:1.15.19-3.el9_1.5RLSA-2023:1670
Rocky Linux:8mod_md1:2.0.8-8.module+el8.5.0+695+1fa8055eRLSA-2023:1673
Ubuntu:22.04:LTSapache22.4.52-1ubuntu4.4USN-5942-1
Ubuntu:22.04:LTSapache22.4.52-1ubuntu4.4UBUNTU-CVE-2023-25690

Affected products (as reported)

VendorProductVersions
Apache Software Foundation Apache HTTP Server 2.4.0 – through 2.4.55

Weakness: CWE-444 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References