[Pkg-utopia-maintainers] Bug#1126342: avahi: CVE-2026-24401

[Salvatore Bonaccorso]

Source: avahi
Version: 0.8-17
Severity: important
Tags: security upstream
Forwarded: https://github.com/avahi/avahi/issues/501
X-Debbugs-Cc: carnil at debian.org, Debian Security Team <team at security.debian.org>

Hi,

The following vulnerability was published for avahi.

CVE-2026-24401[0]:
| 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.


If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2026-24401
    https://www.cve.org/CVERecord?id=CVE-2026-24401
[1] https://github.com/avahi/avahi/issues/501
[2] https://github.com/avahi/avahi/security/advisories/GHSA-h4vp-5m8j-f6w3
[3] https://github.com/avahi/avahi/commit/78eab31128479f06e30beb8c1cbf99dd921e2524

Please adjust the affected versions in the BTS as needed.

Regards,
Salvatore