Reachable assertion in Avahi - CVE-2026-34933

Vulnerability identifier: #VU125663

CSH Severity: Low

CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-34933

CWE-ID: CWE-617

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to reachable assertion in transport_flags_from_domain() when handling D-Bus method calls with conflicting publish flags. A local user can send a specially crafted D-Bus method call to cause a denial of service.

The issue can be triggered through org.freedesktop.Avahi.EntryGroup methods that accept a flags parameter, and repeated crashes can result in persistent service disruption if the daemon is automatically restarted.

Avahi
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Micro for Rancher
SUSE Linux Enterprise Micro
SUSE Linux Micro
Ubuntu
SUSE Package Hub 15
Basesystem Module
Desktop Applications Module
openSUSE Leap
openEuler
Anolis OS
avahi (Ubuntu package)
avahi-lang
avahi-debugsource
avahi-utils-debuginfo
libavahi-common3-debuginfo
avahi-debuginfo-32bit
avahi-debuginfo
libdns_sd-debuginfo-32bit
avahi-utils
libavahi-core7-debuginfo
avahi-compat-mDNSResponder-devel
libdns_sd-32bit
libavahi-core7
libavahi-devel
libavahi-client3-32bit
libavahi-client3
avahi-compat-howl-devel
libavahi-common3-32bit
libavahi-client3-debuginfo-32bit
libavahi-client3-debuginfo
libavahi-common3-debuginfo-32bit
libdns_sd
libavahi-common3
avahi
libdns_sd-debuginfo
avahi-gobject-devel
avahi-gobject
avahi-glib
avahi-dnsconfd
avahi-devel
avahi-compat-libdns_sd-devel
avahi-compat-libdns_sd
avahi-compat-howl
avahi-autoipd
avahi-glib-devel
avahi-qt5
avahi-libs
avahi-qt5-devel
avahi-tools
avahi-ui-devel
avahi-ui-gtk3
avahi-ui-tools
python3-avahi
avahi-help
avahi-ui
libavahi-ui-gtk3-0-debuginfo
libavahi-glib1-debuginfo
libhowl0-debuginfo
libavahi-ui-gtk3-0
libavahi-qt5-devel
avahi-utils-gtk
libavahi-glib1
avahi-utils-gtk-debuginfo
avahi-qt5-debugsource
libavahi-qt5-1-debuginfo
libavahi-gobject-devel
libavahi-libevent1
python3-avahi-gtk
libhowl0
typelib-1_0-Avahi-0_6
libavahi-glib-devel
avahi-glib2-debugsource
avahi-32bit-debuginfo
libavahi-glib1-64bit
libavahi-common3-64bit-debuginfo
libavahi-common3-64bit
libdns_sd-64bit-debuginfo
libavahi-client3-64bit-debuginfo
libavahi-glib1-64bit-debuginfo
libdns_sd-64bit
libavahi-client3-64bit
avahi-64bit-debuginfo
libavahi-common3-32bit-debuginfo
libavahi-glib1-32bit-debuginfo
libavahi-glib1-32bit
libavahi-gobject0-debuginfo
libdns_sd-32bit-debuginfo
libavahi-client3-32bit-debuginfo
libavahi-libevent1-debuginfo
libavahi-gobject0
libavahi-qt5-1
avahi-autoipd-debuginfo

Install security update from vendor's website.

Avahi - update to 0.9 rc4
avahi (Ubuntu package) - addressed in versions 0.6.31-4ubuntu1.3+esm5, 0.6.32~rc+dfsg-1ubuntu2.3+esm5, 0.7-3.1ubuntu1.3+esm4, 0.7-4ubuntu7.3+esm2, 0.8-5ubuntu5.5, 0.8-13ubuntu6.2, 0.8-16ubuntu3.2, 0.8-18ubuntu1.1
avahi-lang - addressed in versions 0.6.32-32.42.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-debugsource - addressed in versions 0.6.32-32.42.1, 0.8-9.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-utils-debuginfo - addressed in versions 0.6.32-32.42.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-common3-debuginfo - addressed in versions 0.6.32-32.42.1, 0.8-9.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-debuginfo-32bit - update to 0.6.32-32.42.1
avahi-debuginfo - addressed in versions 0.6.32-32.42.1, 0.8-9.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
libdns_sd-debuginfo-32bit - update to 0.6.32-32.42.1
avahi-utils - addressed in versions 0.6.32-32.42.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-core7-debuginfo - addressed in versions 0.6.32-32.42.1, 0.8-9.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-compat-mDNSResponder-devel - addressed in versions 0.6.32-32.42.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
libdns_sd-32bit - addressed in versions 0.6.32-32.42.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-core7 - addressed in versions 0.6.32-32.42.1, 0.8-9.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-devel - addressed in versions 0.6.32-32.42.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-client3-32bit - addressed in versions 0.6.32-32.42.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-client3 - addressed in versions 0.6.32-32.42.1, 0.8-9.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-compat-howl-devel - addressed in versions 0.6.32-32.42.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-common3-32bit - addressed in versions 0.6.32-32.42.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-client3-debuginfo-32bit - update to 0.6.32-32.42.1
libavahi-client3-debuginfo - addressed in versions 0.6.32-32.42.1, 0.8-9.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-common3-debuginfo-32bit - update to 0.6.32-32.42.1
libdns_sd - addressed in versions 0.6.32-32.42.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-common3 - addressed in versions 0.6.32-32.42.1, 0.8-9.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi - addressed in versions 0.6.32-32.42.1, 0.8-9.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
libdns_sd-debuginfo - addressed in versions 0.6.32-32.42.1, 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-gobject-devel - update to 0.8-11
avahi-gobject - update to 0.8-11
avahi-glib - update to 0.8-11
avahi-dnsconfd - update to 0.8-11
avahi-devel - update to 0.8-11
avahi-compat-libdns_sd-devel - update to 0.8-11
avahi-compat-libdns_sd - update to 0.8-11
avahi-compat-howl-devel - update to 0.8-11
avahi-compat-howl - update to 0.8-11
avahi-autoipd - update to 0.8-11
avahi - update to 0.8-11
avahi-glib-devel - update to 0.8-11
avahi-qt5 - update to 0.8-11
avahi-libs - update to 0.8-11
avahi-qt5-devel - update to 0.8-11
avahi-tools - update to 0.8-11
avahi-ui-devel - update to 0.8-11
avahi-ui-gtk3 - update to 0.8-11
avahi-ui-tools - update to 0.8-11
python3-avahi - update to 0.8-11
avahi-help - addressed in versions 0.8-18, 0.8-28
avahi-ui-gtk3 - addressed in versions 0.8-18, 0.8-28
avahi - addressed in versions 0.8-18, 0.8-28
avahi-autoipd - addressed in versions 0.8-18, 0.8-28
avahi-compat-howl - addressed in versions 0.8-18, 0.8-28
avahi-compat-howl-devel - addressed in versions 0.8-18, 0.8-28
avahi-compat-libdns_sd - addressed in versions 0.8-18, 0.8-28
avahi-compat-libdns_sd-devel - addressed in versions 0.8-18, 0.8-28
avahi-debuginfo - addressed in versions 0.8-18, 0.8-28
avahi-debugsource - addressed in versions 0.8-18, 0.8-28
avahi-devel - addressed in versions 0.8-18, 0.8-28
avahi-dnsconfd - addressed in versions 0.8-18, 0.8-28
avahi-glib - addressed in versions 0.8-18, 0.8-28
avahi-glib-devel - addressed in versions 0.8-18, 0.8-28
avahi-gobject - addressed in versions 0.8-18, 0.8-28
avahi-gobject-devel - addressed in versions 0.8-18, 0.8-28
avahi-libs - addressed in versions 0.8-18, 0.8-28
avahi-qt5 - update to 0.8-18
avahi-qt5-devel - update to 0.8-18
avahi-tools - addressed in versions 0.8-18, 0.8-28
avahi-ui - addressed in versions 0.8-18, 0.8-28
avahi-ui-devel - addressed in versions 0.8-18, 0.8-28
avahi-ui-tools - update to 0.8-28
libavahi-ui-gtk3-0-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-autoipd - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-glib1-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libhowl0-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-ui-gtk3-0 - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-qt5-devel - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-utils-gtk - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-glib1 - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-utils-gtk-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-qt5-debugsource - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-qt5-1-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-gobject-devel - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-libevent1 - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
python3-avahi-gtk - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libhowl0 - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
typelib-1_0-Avahi-0_6 - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-glib-devel - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-glib2-debugsource - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-32bit-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-glib1-64bit - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-common3-64bit-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-common3-64bit - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libdns_sd-64bit-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-client3-64bit-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-glib1-64bit-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libdns_sd-64bit - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-client3-64bit - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-64bit-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-common3-32bit-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-glib1-32bit-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-glib1-32bit - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-gobject0-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libdns_sd-32bit-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-client3-32bit-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
python3-avahi - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-libevent1-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-gobject0 - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
libavahi-qt5-1 - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1
avahi-autoipd-debuginfo - addressed in versions 0.8-150400.7.31.2, 0.8-150600.15.18.1

• https://github.com/avahi/avahi/security/advisories/GHSA-w65r-6gxh-vhvc
• https://github.com/advisories/GHSA-w65r-6gxh-vhvc

• Multiple vulnerabilities in Avahi
• openEuler 24.03 LTS SP3 update for avahi
• openEuler 24.03 LTS SP1 update for avahi
• openEuler 24.03 LTS update for avahi
• openEuler 22.03 LTS SP4 update for avahi
• openEuler 20.03 LTS SP4 update for avahi
• openEuler 24.03 LTS SP2 update for avahi
• Anolis OS update for avahi
• SUSE update for avahi
• Ubuntu update for avahi
• SUSE update for avahi
• SUSE update for avahi
• SUSE update for avahi