MediumFix available

avahi — security advisory

Type: advisorySources: OSVAdvisory ID: DEBIAN-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, which is part of version 0.9-rc3.

Products: avahi
Affected versions: 0.8-10, 0.8-10+deb12u1, 0.8-11, 0.8-12, 0.8-13, 0.8-14, 0.8-15, 0.8-16, 0.8-17, 0.8-18
Fixed versions: 0.8-18
CVEs: CVE-2026-24401
Confirmed fixed CVEs: Not specified
Updated in this feed: 1 Nov 2026, 04:05 UTC · Revision 1

Source evidence

DEBIAN-CVE-2026-24401

core-osv · Original source

Published 24 Jan 2026, 02:15 UTC

osv:DEBIAN-CVE-2026-24401

avahi

Fixed versions: Not specified

avahi

Fixed versions: Not specified

avahi

Fixed versions: 0.8-18

Complete source record

{
  "id": "694ca6cff758d636d81de093947742ffe23032ced79643c88d5c6b56a1d95e3a",
  "url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-24401",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "DEBIAN-CVE-2026-24401",
    "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, which is part of version 0.9-rc3.",
    "evidence": "osv:DEBIAN-CVE-2026-24401",
    "products": [
      {
        "name": {
          "value": "avahi",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": [
          {
            "value": "0.8-10",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "0.8-10+deb12u1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "0.8-11",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "0.8-12",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "0.8-13",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "0.8-14",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "0.8-15",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "0.8-16",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "0.8-17",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "0.8-18",
            "evidence": "/affected/0/versions"
          }
        ]
      },
      {
        "name": {
          "value": "avahi",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": [
          {
            "value": "0.8-16",
            "evidence": "/affected/1/versions"
          },
          {
            "value": "0.8-17",
            "evidence": "/affected/1/versions"
          },
          {
            "value": "0.8-18",
            "evidence": "/affected/1/versions"
          }
        ]
      },
      {
        "name": {
          "value": "avahi",
          "evidence": "/affected/2/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "0.8-18",
            "evidence": "/affected/2/ranges"
          }
        ],
        "affected_versions": [
          {
            "value": "0.8-16",
            "evidence": "/affected/2/versions"
          },
          {
            "value": "0.8-17",
            "evidence": "/affected/2/versions"
          }
        ]
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "DEBIAN-CVE-2026-24401",
      "aliases": [
        "DEBIAN-CVE-2026-24401"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                }
              ]
            }
          ],
          "package": {
            "name": "avahi",
            "purl": "pkg:deb/debian/avahi?arch=source&distro=bookworm",
            "ecosystem": "Debian:12"
          },
          "versions": [
            "0.8-10",
            "0.8-10+deb12u1",
            "0.8-11",
            "0.8-12",
            "0.8-13",
            "0.8-14",
            "0.8-15",
            "0.8-16",
            "0.8-17",
            "0.8-18"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-24401.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                }
              ]
            }
          ],
          "package": {
            "name": "avahi",
            "purl": "pkg:deb/debian/avahi?arch=source&distro=trixie",
            "ecosystem": "Debian:13"
          },
          "versions": [
            "0.8-16",
            "0.8-17",
            "0.8-18"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-24401.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "0.8-18"
                }
              ]
            }
          ],
          "package": {
            "name": "avahi",
            "purl": "pkg:deb/debian/avahi?arch=source&distro=forky",
            "ecosystem": "Debian:14"
          },
          "versions": [
            "0.8-16",
            "0.8-17"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-24401.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        }
      ],
      "modified": "2026-10-24T09:47:28.245384853Z",
      "provider": "osv",
      "upstream": [
        "CVE-2026-24401"
      ],
      "references": [
        "https://security-tracker.debian.org/tracker/CVE-2026-24401"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2026-24401",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 428968,
  "published_at": "2026-01-24T02:15:48.76+00:00"
}