CVE-2021-40438

CriticalCVSS 9.0/10Known exploited (CISA KEV)Last modified Aug 6, 2026

Description

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.

Metrics

CVSS 3.1 9.0/10CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

Weakness enumeration

Affected software

VendorProductVersions
Apache Software FoundationApache HTTP Server>= Apache HTTP Server 2.4, <= 2.4.48

References

Timeline

Published
Sep 16, 2021
Last modified
Aug 6, 2026
Added to CISA KEV
Dec 1, 2021
NVD status
Analyzed

Related CVEs from 2021

CVE-2021-40438: Critical severity, CVSS 9.0 | Vulnix