Apache HTTP Server: HTTP request splitting with mod_rewrite and mod_proxy
En bref
Sévérité
CRITICAL 9.8
EPSS
EPSS 84.51 % · centile 100 (2026-10-27)
État
PUBLISHED
Publiée
Mise à jour
Attribuée par
apache
Statut NVD
Modified
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.
