Reachable assertion in Avahi - CVE-2025-68471

Vulnerability identifier: #VU127433

CSH Severity: Medium

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

CVE-ID: CVE-2025-68471

CWE-ID: CWE-617

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 reachable assertion in lookup_start when processing unsolicited multicast DNS announcements with CNAME resource records. A remote attacker can send two specially crafted unsolicited announcements to cause a denial of service.

The issue affects record browsers where AVAHI_LOOKUP_USE_MULTICAST is set explicitly, and user interaction is required.

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

Install security update from vendor's website.

Avahi - update to 0.9 rc3
avahi (Ubuntu package) - addressed in versions 0.6.31-4ubuntu1.3+esm4, 0.6.32~rc+dfsg-1ubuntu2.3+esm4, 0.7-3.1ubuntu1.3+esm3, 0.7-4ubuntu7.3+esm1, 0.8-5ubuntu5.4, 0.8-13ubuntu6.1, 0.8-16ubuntu3.1
avahi-compat-mDNSResponder-devel - addressed in versions 0.6.32-32.36.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-common3-debuginfo - addressed in versions 0.6.32-32.36.1, 0.7-150100.3.46.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libdns_sd-debuginfo - addressed in versions 0.6.32-32.36.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi-debuginfo - addressed in versions 0.6.32-32.36.1, 0.7-150100.3.46.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-common3 - addressed in versions 0.6.32-32.36.1, 0.7-150100.3.46.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libdns_sd-32bit - addressed in versions 0.6.32-32.36.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-client3-32bit - addressed in versions 0.6.32-32.36.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-devel - addressed in versions 0.6.32-32.36.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libdns_sd - addressed in versions 0.6.32-32.36.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi-utils - addressed in versions 0.6.32-32.36.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-client3-debuginfo - addressed in versions 0.6.32-32.36.1, 0.7-150100.3.46.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-common3-debuginfo-32bit - update to 0.6.32-32.36.1
avahi-debugsource - addressed in versions 0.6.32-32.36.1, 0.7-150100.3.46.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi-compat-howl-devel - addressed in versions 0.6.32-32.36.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi - addressed in versions 0.6.32-32.36.1, 0.7-150100.3.46.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-client3-debuginfo-32bit - update to 0.6.32-32.36.1
avahi-utils-debuginfo - addressed in versions 0.6.32-32.36.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-core7-debuginfo - addressed in versions 0.6.32-32.36.1, 0.7-150100.3.46.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-client3 - addressed in versions 0.6.32-32.36.1, 0.7-150100.3.46.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi-debuginfo-32bit - update to 0.6.32-32.36.1
libavahi-core7 - addressed in versions 0.6.32-32.36.1, 0.7-150100.3.46.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-common3-32bit - addressed in versions 0.6.32-32.36.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
libdns_sd-debuginfo-32bit - update to 0.6.32-32.36.1
avahi-lang - addressed in versions 0.6.32-32.36.1, 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi-compat-libdns_sd-devel - update to 0.8-9
avahi - update to 0.8-9
avahi-autoipd - update to 0.8-9
avahi-compat-howl - update to 0.8-9
avahi-compat-howl-devel - update to 0.8-9
avahi-compat-libdns_sd - update to 0.8-9
avahi-devel - update to 0.8-9
avahi-dnsconfd - update to 0.8-9
avahi-glib - update to 0.8-9
avahi-gobject - update to 0.8-9
python3-avahi - update to 0.8-9
avahi-ui-tools - update to 0.8-9
avahi-ui-gtk3 - update to 0.8-9
avahi-ui-devel - update to 0.8-9
avahi-tools - update to 0.8-9
avahi-qt5-devel - update to 0.8-9
avahi-qt5 - update to 0.8-9
avahi-libs - update to 0.8-9
avahi-gobject-devel - update to 0.8-9
avahi-glib-devel - update to 0.8-9
avahi-autoipd - update to 0.8-15
avahi-compat-howl - update to 0.8-15
avahi-help - update to 0.8-15
avahi-ui-gtk3 - update to 0.8-15
avahi-ui-devel - update to 0.8-15
avahi-ui - update to 0.8-15
avahi-tools - update to 0.8-15
avahi-qt5-devel - update to 0.8-15
avahi - update to 0.8-15
avahi-qt5 - update to 0.8-15
avahi-libs - update to 0.8-15
avahi-gobject-devel - update to 0.8-15
avahi-gobject - update to 0.8-15
avahi-glib-devel - update to 0.8-15
avahi-glib - update to 0.8-15
avahi-dnsconfd - update to 0.8-15
avahi-devel - update to 0.8-15
avahi-debugsource - update to 0.8-15
avahi-debuginfo - update to 0.8-15
avahi-compat-libdns_sd-devel - update to 0.8-15
avahi-compat-libdns_sd - update to 0.8-15
avahi-compat-howl-devel - update to 0.8-15
libavahi-gobject0-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi-qt5-debugsource - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi-utils-gtk - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-glib1-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi-glib2-debugsource - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-qt5-1-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
typelib-1_0-Avahi-0_6 - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libhowl0-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi-autoipd-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-glib-devel - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-qt5-1 - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
python3-avahi - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi-autoipd - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-ui-gtk3-0 - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-libevent1-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-qt5-devel - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libdns_sd-64bit - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi-64bit-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-client3-64bit - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-client3-64bit-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-client3-32bit-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi-32bit-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-common3-32bit-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-gobject0 - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-glib1-32bit - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libdns_sd-32bit-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-glib1-32bit-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-glib1 - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-libevent1 - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-gobject-devel - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
avahi-utils-gtk-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-ui-gtk3-0-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
python3-avahi-gtk - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libdns_sd-64bit-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-glib1-64bit - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-common3-64bit-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-common3-64bit - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libavahi-glib1-64bit-debuginfo - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1
libhowl0 - addressed in versions 0.8-150400.7.26.1, 0.8-150600.15.12.1

• https://github.com/avahi/avahi/security/advisories/GHSA-56rf-42xr-qmmg

• Multiple vulnerabilities in Avahi
• openEuler update for avahi
• SUSE update for avahi
• SUSE update for avahi
• SUSE update for avahi
• SUSE update for avahi
• Anolis OS update for avahi
• Ubuntu update for avahi