{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "FlashMQ",
          "vendor": "halfgaar",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.26.1"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "FlashMQ is a MQTT broker/server, designed for multi-CPU environments. Prior to version 1.26.1, a remote client with retained publish permission can crash the FlashMQ broker when both set_retained_message_defer_timeout and set_retained_message_defer_timeout_spread are configured to non-default values, resulting in denial of service. If anonymous retained publishing is allowed, no authentication is required; otherwise, the attacker needs the corresponding publish permission. This issue has been patched in version 1.26.1."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-369",
              "description": "CWE-369: Divide By Zero",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-08T21:40:43.284Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/halfgaar/FlashMQ/security/advisories/GHSA-2789-vfcg-5922",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/halfgaar/FlashMQ/security/advisories/GHSA-2789-vfcg-5922"
        },
        {
          "name": "https://github.com/halfgaar/FlashMQ/issues/167",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/halfgaar/FlashMQ/issues/167"
        },
        {
          "name": "https://github.com/halfgaar/FlashMQ/commit/193b6e7767889511cfa8e933908ea5e6a1077a1f",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/halfgaar/FlashMQ/commit/193b6e7767889511cfa8e933908ea5e6a1077a1f"
        },
        {
          "name": "https://github.com/halfgaar/FlashMQ/releases/tag/v1.26.1",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/halfgaar/FlashMQ/releases/tag/v1.26.1"
        }
      ],
      "source": {
        "advisory": "GHSA-2789-vfcg-5922",
        "discovery": "UNKNOWN"
      },
      "title": "FlashMQ: Division by zero crash when using non-default deferred retained message setting"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-42209",
    "datePublished": "2026-05-08T21:40:43.284Z",
    "dateReserved": "2026-04-25T05:04:37.028Z",
    "dateUpdated": "2026-05-08T21:40:43.284Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-42209",
      "date": "2026-05-10",
      "epss": "0.00115",
      "percentile": "0.29793"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-42209\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-05-08T22:16:32.103\",\"lastModified\":\"2026-05-08T22:16:32.103\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"FlashMQ is a MQTT broker/server, designed for multi-CPU environments. Prior to version 1.26.1, a remote client with retained publish permission can crash the FlashMQ broker when both set_retained_message_defer_timeout and set_retained_message_defer_timeout_spread are configured to non-default values, resulting in denial of service. If anonymous retained publishing is allowed, no authentication is required; otherwise, the attacker needs the corresponding publish permission. This issue has been patched in version 1.26.1.\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":6.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":2.8,\"impactScore\":3.6}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-369\"}]}],\"references\":[{\"url\":\"https://github.com/halfgaar/FlashMQ/commit/193b6e7767889511cfa8e933908ea5e6a1077a1f\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/halfgaar/FlashMQ/issues/167\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/halfgaar/FlashMQ/releases/tag/v1.26.1\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/halfgaar/FlashMQ/security/advisories/GHSA-2789-vfcg-5922\",\"source\":\"security-advisories@github.com\"}]}}"
  }
}