CVE-2025-68471 Avahi has a reachable assertion in lookup_start
An attacker can crash the Avahi daemon by sending specific unsolicited mDNS announcements, causing a denial of service for local network service discovery.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2025-68471?
CVE-2025-68471 is a medium-severity denial of service vulnerability in avahi, published on 12 Jan 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-617
Which versions are affected by CVE-2025-68471?
It affects 1 product.
Products include Avahi Avahi.
How do I fix CVE-2025-68471?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-68471 being exploited?
There is no known exploitation of CVE-2025-68471 in the wild and no public exploit code.
Other vulnerabilities in avahi
- CVE-2017-6519 Denial of service in n/a
- CVE-2021-26720 Path traversal in n/a
- CVE-2026-24401 Avahi has Uncontrolled Recursion in lookup_handle_cname function
- CVE-2025-68468 Avahi has a reachable assertion in lookup_multicast_callback
- CVE-2023-38469 Reachable assertion in avahi_dns_packet_append_record
Sources
Also known as ALPINE-CVE-2025-68471, AZL-74277, AZL-74291, BELL-CVE-2025-68471, DEBIAN-CVE-2025-68471, ECHO-b6a0-85de-738f and 4 more.