Allocation of Resources Without Limits or Throttling in Apache HTTP Server - CVE-2026-29168

Vulnerability identifier: #VU129547

CSH Severity: Medium

CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-29168

CWE-ID: CWE-770

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to allocation of resources without limits or throttling in mod_md when processing OCSP response data. A remote attacker can provide crafted OCSP response data to cause a denial of service.

Apache HTTP Server
SUSE Linux Enterprise Server 15 SP5
SUSE Linux Enterprise Server 15 SP4
Debian Linux
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise High Performance Computing LTSS 15
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise High Performance Computing ESPOS 15
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Desktop 15
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
SUSE Package Hub 15
Server Applications Module
Basesystem Module
openSUSE Leap
openEuler
Ubuntu
Fedora
md (Red Hat package)
mod_proxy_html
mod_md
mod_ldap
httpd-tools
httpd-devel
httpd-debugsource
httpd-debuginfo
httpd
httpd-help
httpd-filesystem
mod_ssl
mod_session
apache2 (Ubuntu package)
apache2-tls13-worker-debuginfo
apache2-tls13-utils-debuginfo
apache2-tls13
apache2-tls13-debuginfo
apache2-tls13-debugsource
apache2-tls13-worker
apache2-debuginfo
apache2
apache2-tls13-example-pages
apache2-utils-debuginfo
apache2-tls13-prefork
apache2-debugsource
apache2-devel
apache2-tls13-devel
apache2-prefork
apache2-tls13-prefork-debuginfo
apache2-worker
apache2-prefork-debuginfo
apache2-example-pages
apache2-tls13-utils
apache2-worker-debuginfo
apache2-doc
apache2-tls13-doc
apache2-utils
apache2-event-debuginfo
apache2-event
apache2-utils-debugsource
apache2-manual
apache2-prefork-debugsource
apache2-worker-debugsource
apache2-event-debugsource
apache2 (Debian package)

Install security update from vendor's website.

Apache HTTP Server - update to 2.4.67
md (Red Hat package) - update to 2.4.26-5.el10_2.1
mod_proxy_html - addressed in versions 2.4.43-35, 2.4.51-29, 2.4.58-14, 2.4.58-15
mod_md - addressed in versions 2.4.43-35, 2.4.51-29, 2.4.58-14, 2.4.58-15
mod_ldap - addressed in versions 2.4.43-35, 2.4.51-29, 2.4.58-14, 2.4.58-15
httpd-tools - addressed in versions 2.4.43-35, 2.4.51-29, 2.4.58-14, 2.4.58-15
httpd-devel - addressed in versions 2.4.43-35, 2.4.51-29, 2.4.58-14, 2.4.58-15
httpd-debugsource - addressed in versions 2.4.43-35, 2.4.51-29, 2.4.58-14, 2.4.58-15
httpd-debuginfo - addressed in versions 2.4.43-35, 2.4.51-29, 2.4.58-14, 2.4.58-15
httpd - addressed in versions 2.4.43-35, 2.4.51-29, 2.4.58-14, 2.4.58-15
httpd-help - addressed in versions 2.4.43-35, 2.4.51-29, 2.4.58-14, 2.4.58-15
httpd-filesystem - addressed in versions 2.4.43-35, 2.4.51-29, 2.4.58-14, 2.4.58-15
mod_ssl - addressed in versions 2.4.43-35, 2.4.51-29, 2.4.58-14, 2.4.58-15
mod_session - addressed in versions 2.4.43-35, 2.4.51-29, 2.4.58-14, 2.4.58-15
apache2 (Ubuntu package) - addressed in versions 2.4.52-1ubuntu4.20, 2.4.58-1ubuntu8.12, 2.4.64-1ubuntu3.4, 2.4.66-2ubuntu2.1
apache2-tls13-worker-debuginfo - update to 2.4.66-35.78.1
apache2-tls13-utils-debuginfo - update to 2.4.66-35.78.1
apache2-tls13 - update to 2.4.66-35.78.1
apache2-tls13-debuginfo - update to 2.4.66-35.78.1
apache2-tls13-debugsource - update to 2.4.66-35.78.1
apache2-tls13-worker - update to 2.4.66-35.78.1
apache2-debuginfo - addressed in versions 2.4.66-35.78.1, 2.4.66-150400.6.57.1, 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2 - addressed in versions 2.4.66-35.78.1, 2.4.66-150400.6.57.1, 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-tls13-example-pages - update to 2.4.66-35.78.1
apache2-utils-debuginfo - addressed in versions 2.4.66-35.78.1, 2.4.66-150400.6.57.1, 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-tls13-prefork - update to 2.4.66-35.78.1
apache2-debugsource - addressed in versions 2.4.66-35.78.1, 2.4.66-150400.6.57.1, 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-devel - addressed in versions 2.4.66-35.78.1, 2.4.66-150400.6.57.1, 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-tls13-devel - update to 2.4.66-35.78.1
apache2-prefork - addressed in versions 2.4.66-35.78.1, 2.4.66-150400.6.57.1, 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-tls13-prefork-debuginfo - update to 2.4.66-35.78.1
apache2-worker - addressed in versions 2.4.66-35.78.1, 2.4.66-150400.6.57.1, 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-prefork-debuginfo - addressed in versions 2.4.66-35.78.1, 2.4.66-150400.6.57.1, 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-example-pages - addressed in versions 2.4.66-35.78.1, 2.4.66-150400.6.57.1
apache2-tls13-utils - update to 2.4.66-35.78.1
apache2-worker-debuginfo - addressed in versions 2.4.66-35.78.1, 2.4.66-150400.6.57.1, 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-doc - addressed in versions 2.4.66-35.78.1, 2.4.66-150400.6.57.1
apache2-tls13-doc - update to 2.4.66-35.78.1
apache2-utils - addressed in versions 2.4.66-35.78.1, 2.4.66-150400.6.57.1, 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-event-debuginfo - addressed in versions 2.4.66-150400.6.57.1, 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-event - addressed in versions 2.4.66-150400.6.57.1, 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-utils-debugsource - addressed in versions 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-manual - addressed in versions 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-prefork-debugsource - addressed in versions 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-worker-debugsource - addressed in versions 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2-event-debugsource - addressed in versions 2.4.66-150600.5.52.1, 2.4.66-150700.4.20.1
apache2 (Debian package) - addressed in versions 2.4.67-1~deb12u2, 2.4.67-1~deb13u2
mod_md - addressed in versions 2.6.11-2.fc43, 2.6.11-2.fc44

• https://httpd.apache.org/security/vulnerabilities_24.html#CVE-2026-29168

• Multiple vulnerabilities in Apache HTTP Server
• Ubuntu update for apache2
• Fedora 44 update for mod_md
• Fedora 43 update for mod_md
• Debian update for apache2
• openEuler 24.03 LTS SP1 update for httpd
• openEuler 24.03 LTS update for httpd
• openEuler 22.03 LTS SP4 update for httpd
• openEuler 24.03 LTS SP3 update for httpd
• openEuler 20.03 LTS SP4 update for httpd
• SUSE update for apache2
• SUSE update for apache2
• SUSE update for apache2
• Red Hat Enterprise Linux 10 update for mod_md
• SUSE update for apache2