Live › vulnerability › CVE-2021-40438
Go to dashboardApache HTTP Server's mod_proxy can be tricked by a crafted request URI into forwarding the request to a backend server the remote user picks. An attacker can use the server as a proxy to reach internal services that the server itself can access.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 19:11 UTC, 3h before NVD. All times on this page are UTC.
Apply updates per vendor instructions.
| Product | Ecosystem | Affected | Fixed in |
|---|---|---|---|
| Apache Apache | vendor | – | – |
2.4.48 or earlierUpgrade Apache HTTP Server to a release later than 2.4.48 per the vendor instructions.
Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
A crafted request uri-path can cause mod_proxy to forward the request to an origin server choosen by the remote user. This issue affects Apache HTTP Server 2.4.48 and earlier.
CISA required action: Apply updates per vendor instructions.
This page as .md · .json · in your agent: get_signal("CVE-2021-40438")
CISA KEV catalog, Creative Commons 0 · EPSS scores by FIRST, used with attribution · NVD data is provided by NIST and is public domain. Posts quoted belong to their authors.