CVE-2026-24401 (GCVE-0-2026-24401)

Vulnerability from cvelistv5 – Published: 2026-01-24 01:25 – Updated: 2026-01-26 16:17
VLAI
Title
Avahi has Uncontrolled Recursion in lookup_handle_cname function
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-26 16:14 UTC
CWE
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7643 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
avahi avahi Affected: < 78eab31128479f06e30beb8c1cbf99dd921e2524
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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