CVE-2026-24401
Avahi has Uncontrolled Recursion in lookup_handle_cname function
- State
- Published
- Severity
- 6.5 Medium
- Published
- Jan 24, 2026
- Updated
- Oct 23, 2026
- Reserved
- Jan 22, 2026
Description
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, which is part of version 0.9-rc3.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 6.5 Medium | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H | GitHub_M |
Weaknesses
- CWE-674 Uncontrolled Recursion
Affected Products
| Product | Versions |
|---|---|
avahiavahi |
|
References
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