{"cve":{"cve_id":"CVE-2026-42209","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":0.00355,"epss_percentile":0.27268,"epss_as_of":"2026-06-23","description":"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.","published_at":"2026-05-08T21:40:43.284000Z","last_modified_at":null,"cvss_v3_score":6.5,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cvss_v3_severity":"MEDIUM","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":["CWE-369"],"nvd_references":["https://github.com/halfgaar/FlashMQ/security/advisories/GHSA-2789-vfcg-5922","https://github.com/halfgaar/FlashMQ/issues/167","https://github.com/halfgaar/FlashMQ/commit/193b6e7767889511cfa8e933908ea5e6a1077a1f","https://github.com/halfgaar/FlashMQ/releases/tag/v1.26.1"],"vuln_status":null,"trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:39.878444Z","updated_at":"2026-06-28T23:30:18.882139Z"},"effective_severity":"MEDIUM","badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"L","value_label":"Low"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"N","value_label":"None"},{"metric":"I","name":"Integrity","value":"N","value_label":"None"},{"metric":"A","name":"Availability","value":"H","value_label":"High"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"halfgaar","vendor_name":"halfgaar","product_slug":"flashmq","product_name":"FlashMQ","version_start":"< 1.26.1","version_start_inclusive":true,"version_end":"< 1.26.1","version_end_inclusive":true,"cpe23_uri":"cve5:halfgaar:flashmq:< 1.26.1:< 1.26.1"}],"exploit_refs":[],"news":[],"references":[{"url":"https://github.com/halfgaar/FlashMQ/security/advisories/GHSA-2789-vfcg-5922","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://github.com/halfgaar/FlashMQ/issues/167","source_type":"MISC","tags":[]},{"url":"https://github.com/halfgaar/FlashMQ/commit/193b6e7767889511cfa8e933908ea5e6a1077a1f","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/halfgaar/FlashMQ/releases/tag/v1.26.1","source_type":"PATCH","tags":["patch"]}],"timeline":[{"type":"published","at":"2026-05-08T21:40:43.284000Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:54:07.258310Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:54:07.258310Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:54:07.258310Z","label":"CVSS score revised","source":"cvelistv5"}]}