CVE-2021-40438

Summary

CVECVE-2021-40438
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-09-16 15:15:00 UTC
Updated2023-11-07 03:38:00 UTC
DescriptionA 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.

Risk And Classification

EPSS: 0.944320000 probability, percentile 0.999850000 (date 2026-04-01)

CISA KEV: Listed on 2021-12-01; due 2021-12-15; ransomware use Unknown

Problem Types: CWE-918

CISA Known Exploited Vulnerability

VendorApache
ProductApache
NameApache HTTP Server-Side Request Forgery (SSRF)
Required ActionApply updates per vendor instructions.
Noteshttps://nvd.nist.gov/vuln/detail/CVE-2021-40438

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Apache Http Server All All All All
Operating System Debian Debian Linux 10.0 All All All
Operating System Debian Debian Linux 11.0 All All All
Operating System Debian Debian Linux 9.0 All All All
Operating System F5 F5os All All All All
Operating System F5 F5os All All All All
Operating System Fedoraproject Fedora 34 All All All
Operating System Fedoraproject Fedora 35 All All All
Application Netapp Cloud Backup - All All All
Application Netapp Clustered Data Ontap - All All All
Application Netapp Storagegrid - All All All
Application Oracle Enterprise Manager Ops Center 12.4.0.0 All All All
Application Oracle Http Server 12.2.1.3.0 All All All
Application Oracle Http Server 12.2.1.4.0 All All All
Application Oracle Instantis Enterprisetrack 17.1 All All All
Application Oracle Instantis Enterprisetrack 17.2 All All All
Application Oracle Instantis Enterprisetrack 17.3 All All All
Application Oracle Secure Global Desktop 5.6 All All All
Application Oracle Zfs Storage Appliance Kit 8.8 All All All
Application Siemens Sinec Nms All All All All
Application Siemens Sinema Server 14.0 - All All

References

ReferenceSourceLinkTags
September 2021 Apache HTTP Server Vulnerabilities in NetApp Products | NetApp Product Security CONFIRM security.netapp.com
Apache HTTPD: Multiple Vulnerabilities (GLSA 202208-20) — Gentoo security GENTOO security.gentoo.org
[R1] Stand-alone Security Patch Available for Tenable.sc versions 5.16.0 to 5.19.1: Patch 202110.1 - Security Advisory | Tenable® CONFIRM www.tenable.com
[httpd-users] 20211019 [users@httpd] Regarding CVE-2021-40438 lists.apache.org
[SECURITY] Fedora 35 Update: httpd-2.4.49-1.fc35 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
[httpd-users] 20210923 Re: [users@httpd] Re: [External] : [users@httpd] 2.4.49 security fixes: more info lists.apache.org
[httpd-users] 20210923 [users@httpd] 2.4.49 security fixes: more info lists.apache.org
[SECURITY] Fedora 34 Update: httpd-2.4.49-1.fc34 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
Pony Mail! MLIST lists.apache.org
Oracle Critical Patch Update Advisory - April 2022 MISC www.oracle.com
Debian -- Security Information -- DSA-4982-1 apache2 DEBIAN www.debian.org
Pony Mail! MLIST lists.apache.org
[httpd-bugs] 20211008 [Bug 65616] CVE-2021-36160 regression lists.apache.org
Pony Mail! MLIST lists.apache.org
Oracle Critical Patch Update Advisory - January 2022 MISC www.oracle.com
Multiple Vulnerabilities in Apache HTTP Server Affecting Cisco Products: November 2021 CISCO tools.cisco.com
Pony Mail! MLIST lists.apache.org
Apache HTTP Server 2.4 vulnerabilities - The Apache HTTP Server Project MISC httpd.apache.org
Pony Mail! MLIST lists.apache.org
Pony Mail! MLIST lists.apache.org
[httpd-users] 20210923 Re: [users@httpd] 2.4.49 security fixes: more info lists.apache.org
[SECURITY] Fedora 35 Update: httpd-2.4.49-1.fc35 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
[SECURITY] [DLA 2776-1] apache2 security update MLIST lists.debian.org
cert-portal.siemens.com/productcert/pdf/ssa-685781.pdf CONFIRM cert-portal.siemens.com
[httpd-users] 20211019 Re: [users@httpd] Regarding CVE-2021-40438 lists.apache.org
Pony Mail! MLIST lists.apache.org
[httpd-users] 20210923 [users@httpd] Re: [External] : [users@httpd] 2.4.49 security fixes: more info lists.apache.org
[SECURITY] Fedora 34 Update: httpd-2.4.49-1.fc34 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis
CISA Known Exploited Vulnerabilities catalog CISA www.cisa.gov kev

Vendor Comments And Credit

Discovery Credit

LEGACY: The issue was discovered by the Apache HTTP security team while analysing CVE-2021-36160

Legacy QID Mappings

  • 150461 Apache HTTP Server mod_proxy Server Side Request Forgery (SSRF) Vulnerability (CVE-2021-40438)
  • 159418 Oracle Enterprise Linux Security Update for httpd:2.4 (ELSA-2021-3816)
  • 159419 Oracle Enterprise Linux Security Update for httpd (ELSA-2021-3856)
  • 178815 Debian Security Update for apache2 (DLA 2776-1)
  • 178819 Debian Security Update for apache2 (DSA 4982-1)
  • 182834 Debian Security Update for apache2 (CVE-2021-40438)
  • 198516 Ubuntu Security Notification for Apache Hypertext Transfer Protocol (HTTP) Server Vulnerabilities (USN-5090-1)
  • 239667 Red Hat Update for httpd24-httpd (RHSA-2021:3754)
  • 239668 Red Hat Update for Red Hat JBoss Core Services Apache Hypertext Transfer Protocol Server (HTTP Server) 2.4.37 SP9 (RHSA-2021:3746)
  • 239671 Red Hat Update for httpd:2.4 (RHSA-2021:3816)
  • 239681 Red Hat Update for httpd (RHSA-2021:3856)
  • 239686 Red Hat Update for httpd:2.4 (RHSA-2021:3837)
  • 239687 Red Hat Update for httpd:2.4 (RHSA-2021:3836)
  • 239871 Red Hat Update for httpd:2.4 (RHSA-2021:4537)
  • 257120 CentOS Security Update for httpd (CESA-2021:3856)
  • 281910 Fedora Security Update for Hypertext Transfer Protocol Daemon (HTTPd) (FEDORA-2021-dce7e7738e)
  • 352857 Amazon Linux Security Advisory for httpd24: ALAS-2021-1543
  • 352858 Amazon Linux Security Advisory for httpd: ALAS2-2021-1716
  • 375988 Apache Hypertext Transfer Protocol (HTTP) Server Multiple Vulnerabilities
  • 376041 IBM Hypertext Transfer Protocol (HTTP) Server Multiple Vulnerabilities (6493841)
  • 376256 Oracle Hypertext Transfer Protocol Server (HTTP Server) Multiple Vulnerabilities (CPUJAN2022)
  • 376381 IBM Hypertext Transfer Protocol (HTTP) Server Multiple Vulnerabilities (6493845,6493841)
  • 376961 NetApp Clustered Data Open Network Technology for Appliance Products (ONTAP) Disclosure of Sensitive Information Vulnerability (NTAP-20211008-0004)
  • 377000 Alibaba Cloud Linux Security Update for httpd (ALINUX2-SA-2021:0059)
  • 377101 Alibaba Cloud Linux Security Update for httpd:2.4 (ALINUX3-SA-2021:0074)
  • 378336 Zimbra Collaboration Suite (ZCS) Multiple Vulnerabilities
  • 38856 Cisco TelePresence Video Communication Server (VCS) Apache Hypertext Transfer Protocol Server (HTTP Server) Vulnerability (cisco-sa-apache-httpd-2.4.49-VWL69sWQ)
  • 500022 Alpine Linux Security Update for apache2
  • 503713 Alpine Linux Security Update for apache2
  • 591221 Siemens SINEC NMS and SINEMA Server Multiple Vulnerabilities (SSA-685781 V1.1)
  • 671157 EulerOS Security Update for httpd (EulerOS-SA-2021-2803)
  • 671166 EulerOS Security Update for httpd (EulerOS-SA-2021-2915)
  • 671168 EulerOS Security Update for httpd (EulerOS-SA-2021-2923)
  • 671190 EulerOS Security Update for httpd (EulerOS-SA-2021-2931)
  • 671266 EulerOS Security Update for httpd (EulerOS-SA-2022-1167)
  • 671293 EulerOS Security Update for httpd (EulerOS-SA-2022-1206)
  • 671333 EulerOS Security Update for httpd (EulerOS-SA-2022-1225)
  • 690025 Free Berkeley Software Distribution (FreeBSD) Security Update for apache httpd (882a38f9-17dd-11ec-b335-d4c9ef517024)
  • 710595 Gentoo Linux Apache HTTPD Multiple Vulnerabilities (GLSA 202208-20)
  • 730209 Apache Hypertext Transfer Protocol Server (HTTP Server) Multiple Vulnerabilities
  • 731099 Hewlett Packard Enterprise (HPE) OneView Multiple Vulnerabilities (HPESBGN04586)
  • 751198 SUSE Enterprise Linux Security Update for apache2 (SUSE-SU-2021:3299-1)
  • 751216 SUSE Enterprise Linux Security Update for apache2 (SUSE-SU-2021:3335-1)
  • 751279 OpenSUSE Security Update for apache2 (openSUSE-SU-2021:3522-1)
  • 751314 OpenSUSE Security Update for apache2 (openSUSE-SU-2021:1438-1)
  • 87468 Apache Hypertext Transfer Protocol (HTTP) Server mod_proxy Server-Side Request Forgery (SSRF) Vulnerability
  • 87470 IBM Hypertext Transfer Protocol (HTTP) Server Multiple Vulnerabilities (6493841)
  • 900331 Common Base Linux Mariner (CBL-Mariner) Security Update for httpd (5489)
  • 901829 Common Base Linux Mariner (CBL-Mariner) Security Update for httpd (6487-1)
  • 940297 AlmaLinux Security Update for httpd:2.4 (ALSA-2021:3816)
  • 960440 Rocky Linux Security Update for httpd:2.4 (RLSA-2021:3816)
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