NULL pointer dereference in Apache HTTP Server - CVE-2021-34798

Vulnerability identifier: #VU56681

CSH Severity: Medium

CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2021-34798

CWE-ID: CWE-476

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error. A remote attacker can send a specially crafted HTTP request to the affected web server and perform a denial of service (DoS) attack.

Apache HTTP Server
IBM HTTP Server
Gentoo Linux
Amazon Linux AMI
F5OS
SUSE CaaS Platform
SUSE Enterprise Storage
Anolis OS
Red Hat Enterprise Linux Server
Red Hat Enterprise Linux Workstation
Red Hat Enterprise Linux Desktop
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, big endian
Red Hat Enterprise Linux for Scientific Computing
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for ARM 64
OpenStack Cloud Crowbar
SUSE OpenStack Cloud
SUSE Linux Enterprise Server
Slackware Linux
Ubuntu
SUSE Linux Enterprise Server for SAP
SUSE Linux Enterprise High Performance Computing
SUSE Linux Enterprise Module for Basesystem
SUSE Linux Enterprise Module for Server Applications
openEuler
Fedora
Brocade Fabric OS
Cisco Security Manager
IBM Security SiteProtector System
Cisco Prime Collaboration Provisioning
EasyApache
Dell Secure Connect Gateway
IBM Rational Build Forge
Oracle HTTP Server
IBM Aspera Orchestrator
EMC NetWorker Server
RUGGEDCOM NMS
SINEMA Remote Connect Server
MELSOFT iQ AppPortal
Traffix SDC
BIG-IP
apache2 (Debian package)
httpd24-httpd (Red Hat package)
SUSE Linux Enterprise Module for Packagehub Subpackages
mod_http2
mod_md
mod_proxy_html
mod_session
mod_ldap
httpd-tools
mod_ssl
httpd-manual
httpd-devel
httpd
httpd24 (Red Hat package)
apache2 (Ubuntu package)
apache2-bin (Ubuntu package)
apache2-prefork
apache2-doc
apache2-worker-debuginfo
apache2-worker
apache2-utils-debuginfo
apache2-utils
apache2-devel
apache2-debugsource
apache2-debuginfo
apache2
apache2-prefork-debuginfo
httpd-filesystem
apache2-event
apache2-event-debuginfo
httpd-debuginfo
httpd-debugsource
httpd-help
app-admin/apache-tools
www-servers/apache
Tenable.sc
IBM Qradar SIEM
IBM Business Automation Manager Open Editions
IBM Aspera Console
XtremIO X2
Maximo Application Suite - IoT Component
CTPView
IBM Aspera Faspex for Linux
IBM Aspera Faspex for Windows
Dell EMC Unity VSA Operating Environment (OE)
Dell EMC Unity Operating Environment (OE)
Dell EMC Unity XT Operating Environment (OE)
IBM Hardware Management Console

Install updates from vendor's website.

Apache HTTP Server - update to 2.4.49
MELSOFT iQ AppPortal - update to 1.29F
apache2 (Debian package) - addressed in versions 2.4.38-3+deb10u6, 2.4.51-1~deb11u1
httpd24-httpd (Red Hat package) - update to 2.4.34-23.el7.5
IBM Security SiteProtector System - update to 3.1.1.17
EasyApache - update to 4 2021-9-22
Dell Secure Connect Gateway - update to 5.12.00.10
Tenable.sc - update to Patch 202110.1
IBM Qradar SIEM - addressed in versions 7.3.3 Fix Pack 10 Interim Fix 02, 7.4.3 Fix Pack 4 Interim Fix 04, 7.5.0 Update Pack 1
IBM Rational Build Forge - update to 8.0.0.21
IBM Business Automation Manager Open Editions - update to 9.0.1
mod_http2 - update to 1.15.7-3
mod_md - update to 2.0.8-8
mod_proxy_html - addressed in versions 2.4.6-97, 2.4.37-43.0.1
mod_session - addressed in versions 2.4.6-97, 2.4.37-43.0.1
mod_ldap - addressed in versions 2.4.6-97, 2.4.37-43.0.1
httpd-tools - addressed in versions 2.4.6-97, 2.4.37-43.0.1
mod_ssl - addressed in versions 2.4.6-97, 2.4.37-43.0.1
httpd-manual - addressed in versions 2.4.6-97, 2.4.37-43.0.1
httpd-devel - addressed in versions 2.4.6-97, 2.4.37-43.0.1
httpd - addressed in versions 2.4.6-97, 2.4.37-43.0.1
httpd24 (Red Hat package) - update to 2.4.6-97.el7_9.4
apache2 (Ubuntu package) - addressed in versions 2.4.29-1ubuntu4.17, 2.4.29-1ubuntu4.18, 2.4.41-4ubuntu3.5, 2.4.41-4ubuntu3.6, 2.4.46-4ubuntu1.2, 2.4.46-4ubuntu1.3, 2.4.182ubuntu3.17+esm2, 2.4.182ubuntu3.17+esm3
apache2-bin (Ubuntu package) - addressed in versions 2.4.29-1ubuntu4.17, 2.4.29-1ubuntu4.18, 2.4.41-4ubuntu3.5, 2.4.41-4ubuntu3.6, 2.4.46-4ubuntu1.2, 2.4.46-4ubuntu1.3, 2.4.182ubuntu3.17+esm2, 2.4.182ubuntu3.17+esm3
apache2-prefork - addressed in versions 2.4.33-3.55.1, 2.4.43-3.32.1
apache2-doc - addressed in versions 2.4.33-3.55.1, 2.4.43-3.32.1
apache2-worker-debuginfo - addressed in versions 2.4.33-3.55.1, 2.4.43-3.32.1
apache2-worker - addressed in versions 2.4.33-3.55.1, 2.4.43-3.32.1
apache2-utils-debuginfo - addressed in versions 2.4.33-3.55.1, 2.4.43-3.32.1
apache2-utils - addressed in versions 2.4.33-3.55.1, 2.4.43-3.32.1
apache2-devel - addressed in versions 2.4.33-3.55.1, 2.4.43-3.32.1
apache2-debugsource - addressed in versions 2.4.33-3.55.1, 2.4.43-3.32.1
apache2-debuginfo - addressed in versions 2.4.33-3.55.1, 2.4.43-3.32.1
apache2 - addressed in versions 2.4.33-3.55.1, 2.4.43-3.32.1
apache2-prefork-debuginfo - addressed in versions 2.4.33-3.55.1, 2.4.43-3.32.1
httpd-filesystem - update to 2.4.37-43.0.1
apache2-event - update to 2.4.43-3.32.1
apache2-event-debuginfo - update to 2.4.43-3.32.1
httpd - update to 2.4.43-9
mod_ssl - update to 2.4.43-9
mod_md - update to 2.4.43-9
httpd-devel - update to 2.4.43-9
httpd-tools - update to 2.4.43-9
httpd-debuginfo - update to 2.4.43-9
mod_ldap - update to 2.4.43-9
mod_proxy_html - update to 2.4.43-9
httpd-debugsource - update to 2.4.43-9
mod_session - update to 2.4.43-9
httpd-help - update to 2.4.43-9
httpd-filesystem - update to 2.4.43-9
httpd - addressed in versions 2.4.49-1.fc34, 2.4.49-1.fc35
app-admin/apache-tools - update to 2.4.54
www-servers/apache - update to 2.4.54
SINEMA Remote Connect Server - update to 3.1
IBM Aspera Console - update to 3.4.2 PL7
IBM Aspera Orchestrator - update to 4.0.1.2b9681
IBM Aspera Faspex for Linux - update to 4.4.2
IBM Aspera Faspex for Windows - update to 4.4.2
Dell EMC Unity VSA Operating Environment (OE) - update to 5.2.0.0.5.173
Dell EMC Unity Operating Environment (OE) - update to 5.2.0.0.5.173
Dell EMC Unity XT Operating Environment (OE) - update to 5.2.0.0.5.173
XtremIO X2 - update to 6.4.1-11
Brocade Fabric OS - addressed in versions 7.4.2j, 8.2.0 CBN5, 8.2.3c, 9.0.1e, 9.1.1
Maximo Application Suite - IoT Component - addressed in versions 8.7.20, 8.8.16, 9.0.6
IBM HTTP Server - update to 9.0.5.10
CTPView - update to 9.1R5
IBM Hardware Management Console - addressed in versions 9.2.952.0, 10.1.1010.0 x86, 10.1.1010.0 ppc
EMC NetWorker Server - addressed in versions 19.5.0.4, 19.6.0

• http://httpd.apache.org/security/vulnerabilities_24.html

• Multiple vulnerabilities in Apache HTTP Server
• Slackware Linux update for httpd
• Multiple vulnerabilities in cPanel EasyApache
• SUSE Linux Enterprise Server update for apache2
• Debian update for apache2
• Denial of service in BIG-IP httpd component
• Denial of service in F5OS httpd component
• Denial of service in Traffix SDC httpd component
• Amazon Linux AMI update for httpd24
• Tenable.sc update for Apache HTTP Server
• Denial of service in Cisco Prime Collaboration Provisioning
• Multiple vulnerabilities in Cisco Security Manager
• Red Hat Enterprise Linux 7 update for httpd
• Denial of service in IBM Rational Build Forge
• IBM QRadar SIEM update for Apache HTTP Server
• Red Hat Enterprise Linux 8 update for the httpd:2.4 module
• Multiple vulnerabilities in IBM Security SiteProtector System
• Multiple vulnerabilities in Mitsubishi Electric MELSOFT iQ AppPortal
• Multiple vulnerabilities in IBM Hardware Management Console
• Multiple vulnerabilities in IBM Hardware Management Console
• NULL pointer dereference in Siemens Products
• SUSE update for apache2
• SUSE update for apache2
• Ubuntu update for apache2
• Ubuntu update for apache2
• Ubuntu update for apache2
• Ubuntu update for apache2
• Multiple vulnerabilities in DELL Secure Connect Gateway Security
• Gentoo update for Apache HTTPD
• Multiple vulnerabilities in IBM HTTP Server
• Brocade Fabric OS update for Apache httpd
• Red Hat Software Collections update for httpd24-httpd
• Multiple vulnerabilities in IBM Aspera Faspex
• Multiple vulnerabilities in Dell EMC NetWorker
• NULL pointer dereference in IBM Aspera Orchestrator
• Multiple vulnerabilities in Oracle HTTP Server
• Multiple vulnerabilities in Dell XtremIO X2
• Multiple vulnerabilities in Dell Unity, Dell UnityVSA, and Dell Unity XT
• Multiple vulnerabilities in IBM Business Automation Manager Open Editions
• Multiple vulnerabilities in Juniper Networks CTPView
• Multiple vulnerabilities in IBM Aspera Console
• openEuler update for httpd
• Fedora 34 update for httpd
• Fedora 35 update for httpd
• Multiple vulnerabilities in IBM Maximo Application Suite - IoT Component
• Anolis OS update for httpd
• Anolis OS update for httpd:2.4 module