VULNERABILITY INTELLIGENCE

CVE-2021-40438

CVSS score9 CRITICAL

EPSS probability100.00%

CISA KEVKnown exploited vulnerability

Published2021-09-16

Last modified2026-08-06

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

Known Exploited Vulnerability

Apache HTTP Server-Side Request Forgery (SSRF)

Vendor / product: Apache / Apache

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.

Weakness classification

security@apache.org: CWE-918
nvd@nist.gov: CWE-918

Primary references

security@apache.org — Third Party Advisory
security@apache.org — Release Notes, Vendor Advisory
security@apache.org — Mailing List
security@apache.org — Mailing List
security@apache.org — Mailing List
security@apache.org — Mailing List
security@apache.org — Mailing List
security@apache.org — Mailing List
security@apache.org — Mailing List
security@apache.org — Mailing List, Third Party Advisory
security@apache.org — Release Notes
security@apache.org — Release Notes