GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2026-34933 (GCVE-0-2026-34933)

Vulnerability from cvelistv5 – Published: 2026-04-03 22:43 – Updated: 2026-04-11 18:09
VLAI
Title
Avahi: Reachable assertion in `transport_flags_from_domain()` via conflicting publish flags crashes avahi-daemon
Summary
Avahi is a system which facilitates service discovery on a local network via the mDNS/DNS-SD protocol suite. Prior to version 0.9-rc4, any unprivileged local user can crash avahi-daemon by sending a single D-Bus method call with conflicting publish flags. This issue has been patched in version 0.9-rc4.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-06 16:09 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
avahi avahi Affected: < 0.9-rc4
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-34933",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-06T16:09:17.006482Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-06T16:09:21.475Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/avahi/avahi/security/advisories/GHSA-w65r-6gxh-vhvc"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2026-04-11T18:09:34.774Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/04/11/9"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "avahi",
          "vendor": "avahi",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.9-rc4"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Avahi is a system which facilitates service discovery on a local network via the mDNS/DNS-SD protocol suite. Prior to version 0.9-rc4, any unprivileged local user can crash avahi-daemon by sending a single D-Bus method call with conflicting publish flags. This issue has been patched in version 0.9-rc4."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 5.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-617",
              "description": "CWE-617: Reachable Assertion",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-03T22:43:26.683Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/avahi/avahi/security/advisories/GHSA-w65r-6gxh-vhvc",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/avahi/avahi/security/advisories/GHSA-w65r-6gxh-vhvc"
        },
        {
          "name": "https://github.com/avahi/avahi/pull/891",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/avahi/avahi/pull/891"
        },
        {
          "name": "https://github.com/avahi/avahi/commit/625ca0fac19229f6dfa3a6c6b698ae657187e50c",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/avahi/avahi/commit/625ca0fac19229f6dfa3a6c6b698ae657187e50c"
        }
      ],
      "source": {
        "advisory": "GHSA-w65r-6gxh-vhvc",
        "discovery": "UNKNOWN"
      },
      "title": "Avahi: Reachable assertion in `transport_flags_from_domain()` via conflicting publish flags crashes avahi-daemon"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-34933",
    "datePublished": "2026-04-03T22:43:26.683Z",
    "dateReserved": "2026-03-31T17:27:08.659Z",
    "dateUpdated": "2026-04-11T18:09:34.774Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-34933",
      "date": "2026-09-16",
      "epss": "0.00203",
      "percentile": "0.10462"
    },
    "microsoft_vex": {
      "current_release_date": "2026-04-14T14:44:57.000Z",
      "cve": "CVE-2026-34933",
      "id": "msrc_CVE-2026-34933",
      "initial_release_date": "2026-04-02T00:00:00.000Z",
      "product_status:fixed": "3",
      "product_status:known_affected": "3",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "Avahi: Reachable assertion in `transport_flags_from_domain()` via conflicting publish flags crashes avahi-daemon",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-34933.json",
      "version": "3"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-34933\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-04-03T23:17:05.377\",\"lastModified\":\"2026-07-24T22:10:00.140\",\"vulnStatus\":\"Analyzed\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Avahi is a system which facilitates service discovery on a local network via the mDNS/DNS-SD protocol suite. Prior to version 0.9-rc4, any unprivileged local user can crash avahi-daemon by sending a single D-Bus method call with conflicting publish flags. This issue has been patched in version 0.9-rc4.\"},{\"lang\":\"es\",\"value\":\"Avahi es un sistema que facilita el descubrimiento de servicios en una red local a trav\u00e9s del conjunto de protocolos mDNS/DNS-SD. Antes de la versi\u00f3n 0.9-rc4, cualquier usuario local sin privilegios puede bloquear avahi-daemon al enviar una \u00fanica llamada a m\u00e9todo D-Bus con indicadores de publicaci\u00f3n en conflicto. Este problema ha sido parcheado en la versi\u00f3n 0.9-rc4.\"}],\"affected\":[{\"source\":\"security-advisories@github.com\",\"affectedData\":[{\"vendor\":\"avahi\",\"product\":\"avahi\",\"versions\":[{\"version\":\"\u003c 0.9-rc4\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":5.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":3.6}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-04-06T16:09:17.006482Z\",\"id\":\"CVE-2026-34933\",\"options\":[{\"exploitation\":\"poc\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-617\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:avahi:avahi:*:*:*:*:*:*:*:*\",\"versionEndExcluding\":\"0.9\",\"matchCriteriaId\":\"6481267F-934F-4A0C-9B25-59738E798458\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:avahi:avahi:0.9:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"76971590-AEED-4CB1-B7B7-45EA8FD11524\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:avahi:avahi:0.9:rc2:*:*:*:*:*:*\",\"matchCriteriaId\":\"83D94AE4-46AC-4955-BB0D-193CF79149A1\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:avahi:avahi:0.9:rc3:*:*:*:*:*:*\",\"matchCriteriaId\":\"42B0E12E-E0CC-47B5-B7D3-9FF12156B68E\"}]}]}],\"references\":[{\"url\":\"https://github.com/avahi/avahi/commit/625ca0fac19229f6dfa3a6c6b698ae657187e50c\",\"source\":\"security-advisories@github.com\",\"tags\":[\"Patch\"]},{\"url\":\"https://github.com/avahi/avahi/pull/891\",\"source\":\"security-advisories@github.com\",\"tags\":[\"Issue Tracking\",\"Patch\"]},{\"url\":\"https://github.com/avahi/avahi/security/advisories/GHSA-w65r-6gxh-vhvc\",\"source\":\"security-advisories@github.com\",\"tags\":[\"Exploit\",\"Patch\",\"Vendor Advisory\"]},{\"url\":\"http://www.openwall.com/lists/oss-security/2026/04/11/9\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Exploit\",\"Mailing List\",\"Third Party Advisory\"]},{\"url\":\"https://github.com/avahi/avahi/security/advisories/GHSA-w65r-6gxh-vhvc\",\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"tags\":[\"Exploit\",\"Patch\",\"Vendor Advisory\"]}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-09-01T12:01:11+00:00",
      "cve": "CVE-2026-34933",
      "id": "CVE-2026-34933",
      "initial_release_date": "2026-04-03T22:43:26.683000+00:00",
      "product_status:fixed": "3",
      "product_status:known_affected": "90",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "avahi: avahi-daemon: Avahi: Denial of Service via D-Bus method call",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34933.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-11T01:26:09Z",
      "cve": "CVE-2026-34933",
      "id": "CVE-2026-34933",
      "initial_release_date": "2026-04-06T23:24:24Z",
      "product_status:known_affected": "843",
      "product_status:recommended": "284",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-34933",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-34933.json",
      "version": "27"
    },
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CVE Program Container\", \"references\": [{\"url\": \"http://www.openwall.com/lists/oss-security/2026/04/11/9\"}], \"providerMetadata\": {\"orgId\": \"af854a3a-2127-422b-91ae-364da2661108\", \"shortName\": \"CVE\", \"dateUpdated\": \"2026-04-11T18:09:34.774Z\"}}, {\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-34933\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-04-06T16:09:17.006482Z\"}}}], \"references\": [{\"url\": \"https://github.com/avahi/avahi/security/advisories/GHSA-w65r-6gxh-vhvc\", \"tags\": [\"exploit\"]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-04-06T16:09:12.363Z\"}}], \"cna\": {\"title\": \"Avahi: Reachable assertion in `transport_flags_from_domain()` via conflicting publish flags crashes avahi-daemon\", \"source\": {\"advisory\": \"GHSA-w65r-6gxh-vhvc\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 5.5, \"attackVector\": \"LOCAL\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"LOW\", \"confidentialityImpact\": \"NONE\"}}], \"affected\": [{\"vendor\": \"avahi\", \"product\": \"avahi\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c 0.9-rc4\"}]}], \"references\": [{\"url\": \"https://github.com/avahi/avahi/security/advisories/GHSA-w65r-6gxh-vhvc\", \"name\": \"https://github.com/avahi/avahi/security/advisories/GHSA-w65r-6gxh-vhvc\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/avahi/avahi/pull/891\", \"name\": \"https://github.com/avahi/avahi/pull/891\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/avahi/avahi/commit/625ca0fac19229f6dfa3a6c6b698ae657187e50c\", \"name\": \"https://github.com/avahi/avahi/commit/625ca0fac19229f6dfa3a6c6b698ae657187e50c\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Avahi is a system which facilitates service discovery on a local network via the mDNS/DNS-SD protocol suite. Prior to version 0.9-rc4, any unprivileged local user can crash avahi-daemon by sending a single D-Bus method call with conflicting publish flags. This issue has been patched in version 0.9-rc4.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-617\", \"description\": \"CWE-617: Reachable Assertion\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-04-03T22:43:26.683Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-34933\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-04-11T18:09:34.774Z\", \"dateReserved\": \"2026-03-31T17:27:08.659Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-04-03T22:43:26.683Z\", \"assignerShortName\": \"GitHub_M\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.