Please note that the fix for CVE-2024-52615 introduces CVE-2025-59529
which is not fixed yet (https://github.com/avahi/avahi/pull/808). You
can mitigate this vulnerability by setting the `enable-wide-area=no`
option.
Patch `0011-properly-randomize-query-id-of-DNS-packets.patch` modify
`configure.ac` and then `AVAHI_AUTORECONF` is set.
This commit fixes the following vulnerabilities:
- CVE-2021-3468:
A flaw was found in avahi in versions 0.6 up to 0.8. The event used to
signal the termination of the client connection on the avahi Unix
socket is not correctly handled in the client_work function, allowing
a local attacker to trigger an infinite loop. The highest threat from
this vulnerability is to the availability of the avahi service, which
becomes unresponsive after this flaw is triggered.
For more information, see:
- https://www.cve.org/CVERecord?id=CVE-2021-3468
- 447affe299
- CVE-2023-38469:
A vulnerability was found in Avahi, where a reachable assertion exists
in avahi_dns_packet_append_record.
https://www.cve.org/CVERecord?id=CVE-2023-38469
- CVE-2023-38470:
A vulnerability was found in Avahi. A reachable assertion exists in
the avahi_escape_label() function.
For more information, see:
- https://www.cve.org/CVERecord?id=CVE-2023-38470
- a337a1ba7d
- CVE-2023-38471:
A vulnerability was found in Avahi. A reachable assertion exists in
the dbus_set_host_name function.
For more information, see:
- https://www.cve.org/CVERecord?id=CVE-2023-38471
- github.com/avahi/avahi/commit/894f085f402e023a98cbb6f5a3d117bd88d93b09
- CVE-2023-38472:
A vulnerability was found in Avahi. A reachable assertion exists in
the avahi_rdata_parse() function.
For more information, see:
- https://www.cve.org/CVERecord?id=CVE-2023-38472
- b024ae5749
- CVE-2023-38473:
A vulnerability was found in Avahi. A reachable assertion exists in
the avahi_alternative_host_name() function.
For more information, see:
- https://www.cve.org/CVERecord?id=CVE-2023-38473
- b448c9f771
- CVE-2024-52615:
A flaw was found in Avahi-daemon, which relies on fixed source ports
for wide-area DNS queries. This issue simplifies attacks where
malicious DNS responses are injected.
For more information, see:
- https://www.cve.org/CVERecord?id=CVE-2024-52615
- 4e2e1ea090
- https://github.com/avahi/avahi/issues/810 (introduce regression CVE-2025-59529)
- CVE-2024-52616:
A flaw was found in the Avahi-daemon, where it initializes DNS
transaction IDs randomly only once at startup, incrementing them
sequentially after that. This predictable behavior facilitates DNS
spoofing attacks, allowing attackers to guess transaction IDs.
For more information, see:
- https://www.cve.org/CVERecord?id=CVE-2024-52616
- f8710bdc8b
- CVE-2025-68276:
Avahi is a system which facilitates service discovery on a local
network via the mDNS/DNS-SD protocol suite. In 0.9-rc2 and earlier, an
unprivileged local users can crash avahi-daemon (with wide-area
disabled) by creating record browsers with the
AVAHI_LOOKUP_USE_WIDE_AREA flag set via D-Bus. This can be done by
either calling the RecordBrowserNew method directly or creating
hostname/address/service resolvers/browsers that create those browsers
internally themselves.
For more information, see:
- https://www.cve.org/CVERecord?id=CVE-2025-68276
- 2d48e42d44
- CVE-2025-68468:
Avahi is a system which facilitates service discovery on a local
network via the mDNS/DNS-SD protocol suite. In 0.9-rc2 and earlier,
avahi-daemon can be crashed by sending unsolicited announcements
containing CNAME resource records pointing it to resource records with
short TTLs. As soon as they expire avahi-daemon crashes.
For more information, see:
- https://www.cve.org/CVERecord?id=CVE-2025-68468
- f66be13d7f
- CVE-2025-68471:
Avahi is a system which facilitates service discovery on a local
network via the mDNS/DNS-SD protocol suite. In 0.9-rc2 and earlier,
avahi-daemon can be crashed by sending 2 unsolicited announcements
with CNAME resource records 2 seconds apart.
For more information, see:
- https://www.cve.org/CVERecord?id=CVE-2025-68471
- 9c6eb53bf2
- CVE-2026-24401:
Avahi is a system which facilitates service discovery on a local
network via the mDNS/DNS-SD protocol suite. In versions 0.9rc2 and
below, avahi-daemon can be crashed via a segmentation fault by sending
an unsolicited mDNS response containing a recursive CNAME record,
where the alias and canonical name point to the same domain (e.g.,
"h.local" as a CNAME for "h.local"). This causes unbounded recursion
in the lookup_handle_cname function, leading to stack exhaustion. The
vulnerability affects record browsers where AVAHI_LOOKUP_USE_MULTICAST
is set explicitly, which includes record browsers created by resolvers
used by nss-mdns. This issue is patched in commit
78eab31128479f06e30beb8c1cbf99dd921e2524.
For more information, see:
- https://www.cve.org/CVERecord?id=CVE-2026-24401
- 78eab31128
Signed-off-by: Thomas Perale <thomas.perale@mind.be>
Signed-off-by: Julien Olivain <ju.o@free.fr>
Thomas Perale