CVEvulnerability

CVE-2021-40438

9.0 CRITICAL Known exploited Published 2021-09-16 Modified 2026-08-06 Official page ↗

CISA Known Exploited Vulnerability

Apache HTTP Server-Side Request Forgery (SSRF) — Apache Apache

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.

Added to KEV
2021-12-01
Remediation due
2021-12-15
Ransomware use
Known
Required action
Apply updates per vendor instructions.
Notes
https://nvd.nist.gov/vuln/detail/CVE-2021-40438
Status
Analyzed
Published
2021-09-16
Last modified
2026-08-06
Assigner
[email protected]
CVSS 3.1 ([email protected])
9.0 CRITICAL — CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
CVSS 3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
9.0 CRITICAL — CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
CVSS 2.0 ([email protected])
6.8 MEDIUM — AV:N/AC:M/Au:N/C:P/I:P/A:P
Weaknesses
CWE-918

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.

Affected configurations

• resf rocky linux 8.0 • redhat enterprise linux 8.0 • redhat enterprise linux eus 8.1 • redhat enterprise linux eus 8.2 • redhat enterprise linux eus 8.4 • redhat enterprise linux eus 8.6 • redhat enterprise linux eus 8.8 • redhat enterprise linux for arm 64 8.0 • redhat enterprise linux for arm 64 eus 8.6 • redhat enterprise linux for arm 64 eus 8.8 • redhat enterprise linux for ibm z systems 7.0 s390x • redhat enterprise linux for ibm z systems 8.0 • redhat enterprise linux for ibm z systems eus 8.1 • redhat enterprise linux for ibm z systems eus 8.4 • redhat enterprise linux for ibm z systems eus 8.8 • redhat enterprise linux for ibm z systems eus s390x 8.2 • redhat enterprise linux for power big endian 7.0 • redhat enterprise linux for power little endian 7.0 • redhat enterprise linux for power little endian 8.0 • redhat enterprise linux for power little endian eus 8.1 • redhat enterprise linux for power little endian eus 8.2 • redhat enterprise linux for power little endian eus 8.4 • redhat enterprise linux for power little endian eus 8.6 • redhat enterprise linux for power little endian eus 8.8 • redhat enterprise linux for scientific computing 7.0 • redhat enterprise linux server 7.0 • redhat enterprise linux server aus 7.2 • redhat enterprise linux server aus 7.3 • redhat enterprise linux server aus 7.4 • redhat enterprise linux server aus 7.6 • redhat enterprise linux server aus 7.7 • redhat enterprise linux server aus 8.2 • redhat enterprise linux server aus 8.4 • redhat enterprise linux server aus 8.6 • redhat enterprise linux server for power little endian update services for sap solutions 7.6 • redhat enterprise linux server for power little endian update services for sap solutions 7.7 • redhat enterprise linux server for power little endian update services for sap solutions 8.1 • redhat enterprise linux server for power little endian update services for sap solutions 8.2 • redhat enterprise linux server for power little endian update services for sap solutions 8.4 • redhat enterprise linux server for power little endian update services for sap solutions 8.6 • redhat enterprise linux server for power little endian update services for sap solutions 8.8 • redhat enterprise linux server tus 7.6 • redhat enterprise linux server tus 7.7 • redhat enterprise linux server tus 8.2 • redhat enterprise linux server tus 8.4 • redhat enterprise linux server tus 8.6 • redhat enterprise linux server tus 8.8 • redhat enterprise linux server update services for sap solutions 7.6 • redhat enterprise linux server update services for sap solutions 7.7 • redhat enterprise linux update services for sap solutions 8.1 • redhat enterprise linux update services for sap solutions 8.2 • redhat enterprise linux update services for sap solutions 8.4 • redhat enterprise linux update services for sap solutions 8.6 • redhat enterprise linux update services for sap solutions 8.8 • redhat enterprise linux workstation 7.0 • redhat jboss core services 1.0 • redhat software collections 1.0 • apache http server (<= 2.4.48) • fedoraproject fedora 34 • fedoraproject fedora 35 … and 23 more

Related

Weakness · CWE (1)

  • CWE-918 Server-Side Request Forgery weakness

References