CVE-2021-33193

Summary

CVECVE-2021-33193
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-08-16 08:15:00 UTC
Updated2023-11-07 03:35:00 UTC
DescriptionA crafted method sent through HTTP/2 will bypass validation and be forwarded by mod_proxy, which can lead to request splitting or cache poisoning. This issue affects Apache HTTP Server 2.4.17 to 2.4.48.

Risk And Classification

Problem Types: NVD-CWE-Other

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Apache Http Server All All All All
Operating System Fedoraproject Fedora 34 All All All
Operating System Fedoraproject Fedora 35 All All All
Application Oracle Secure Backup All All All All
Application Oracle Zfs Storage Appliance Kit 8.8 All All All
Application Tenable Tenable.sc All All All All

References

ReferenceSourceLinkTags
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
[SECURITY] Fedora 34 Update: httpd-2.4.50-1.fc34 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
[SECURITY] Fedora 35 Update: httpd-2.4.50-1.fc35 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
Oracle Critical Patch Update Advisory - April 2022 MISC www.oracle.com
CVE-2021-33193 Apache HTTP Server Vulnerability in NetApp Products | NetApp Product Security CONFIRM security.netapp.com
Pony Mail! MLIST lists.apache.org
Pony Mail! MLIST lists.apache.org
[SECURITY] Fedora 35 Update: httpd-2.4.50-1.fc35 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
[httpd-cvs] 20210916 [httpd-site] branch main updated: Add descriptions for CVE-2021-33193 CVE-2021-36160 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
github.com/apache/httpd/commit/ecebcc035ccd8d0e2984fe41420d9e944f456b3c.... MISC github.com
[SECURITY] [DLA 3351-1] apache2 security update MLIST lists.debian.org
HTTP/2: The Sequel is Always Worse | PortSwigger Research MISC portswigger.net
FEDORA-2021-5d2d4b6ac5 FEDORA lists.fedoraproject.org
[httpd-cvs] 20210916 [httpd-site] branch main updated: Revert "Add descriptions for CVE-2021-33193 CVE-2021-36160" lists.apache.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

LEGACY: Reported by James Kettle of PortSwigger

Legacy QID Mappings

  • 150400 Apache HTTP Server HTTP/2 Method injection (CVE-2021-33193)
  • 159756 Oracle Enterprise Linux Security Update for httpd:2.4 (ELSA-2022-9276)
  • 159811 Oracle Enterprise Linux Security Update for httpd:2.4 (ELSA-2022-1915)
  • 180051 Debian Security Update for apache2 (CVE-2021-33193)
  • 181620 Debian Security Update for apache2 (DLA 3351-1)
  • 198516 Ubuntu Security Notification for Apache Hypertext Transfer Protocol (HTTP) Server Vulnerabilities (USN-5090-1)
  • 240307 Red Hat Update for httpd:2.4 (RHSA-2022:1915)
  • 240698 Red Hat Update for httpd24-httpd (RHSA-2022:6753)
  • 240794 Red Hat Update for JBoss Core Services (RHSA-2022:7143)
  • 281962 Fedora Security Update for httpd (FEDORA-2021-5d2d4b6ac5)
  • 352857 Amazon Linux Security Advisory for httpd24: ALAS-2021-1543
  • 352858 Amazon Linux Security Advisory for httpd: ALAS2-2021-1716
  • 38856 Cisco TelePresence Video Communication Server (VCS) Apache 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
  • 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)
  • 730210 Apache Hypertext Transfer Protocol Server (HTTP Server) HTTP/2 Method Injection Vulnerability
  • 751086 SUSE Enterprise Linux Security Update for apache2 (SUSE-SU-2021:2918-1)
  • 751092 OpenSUSE Security Update for apache2 (openSUSE-SU-2021:2954-1)
  • 751110 OpenSUSE Security Update for apache2 (openSUSE-SU-2021:1234-1)
  • 751216 SUSE Enterprise Linux Security Update for apache2 (SUSE-SU-2021:3335-1)
  • 900317 CBL-Mariner Linux Security Update for httpd 2.4.46
  • 901612 Common Base Linux Mariner (CBL-Mariner) Security Update for httpd (6483-1)
  • 902851 Common Base Linux Mariner (CBL-Mariner) Security Update for httpd (5420)
  • 940509 AlmaLinux Security Update for httpd:2.4 (ALSA-2022:1915)
  • 960327 Rocky Linux Security Update for httpd:2.4 (RLSA-2022:1915)
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