{"id":"CVE-2026-44639","state":"PUBLISHED","title":"NanoMQ: O(N²) Denial of Service in MQTT v5 Property Parsing","description":"NanoMQ is an MQTT broker. Prior to 0.24.14, NanoMQ's MQTT v5 property decoder in nng/src/supplemental/mqtt/mqtt_codec.c uses property_append() to walk the entire linked list for each property added by decode_buf_properties(). A remote unauthenticated client can supply a PUBLISH or SUBSCRIBE packet containing many User Properties, causing O(N²) linked-list insertion and CPU work that makes the broker unresponsive; repeated packets can sustain the denial of service. This issue is fixed in version 0.24.14.","publishedAt":"2026-09-18T16:17:56.222Z","updatedAt":"2026-09-18T17:21:50.284Z","severity":{"score":3.7,"label":"Low","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","source":"GitHub_M"},"assigner":"GitHub_M","products":["nanomq nanomq"],"affected":[{"vendor":"nanomq","product":"nanomq","versions":[{"version":"< 0.24.14","status":"affected"}]}],"references":["https://github.com/nanomq/nanomq/security/advisories/GHSA-6mwg-445v-2qrv","https://github.com/nanomq/NanoNNG/pull/1508","https://github.com/nanomq/NanoNNG/commit/91bd4c7f45f945a3f5f0e37c459157dc7c277a07","https://github.com/nanomq/nanomq/releases/tag/0.24.14"],"weaknesses":["CWE-407"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/44xxx/CVE-2026-44639.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-44639","state":"PUBLISHED","datePublished":"2026-09-18T16:17:56.222Z","dateUpdated":"2026-09-18T17:21:50.284Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-07T15:30:10.875Z"},"containers":{"cna":{"title":"NanoMQ: O(N²) Denial of Service in MQTT v5 Property Parsing","descriptions":[{"lang":"en","value":"NanoMQ is an MQTT broker. Prior to 0.24.14, NanoMQ's MQTT v5 property decoder in nng/src/supplemental/mqtt/mqtt_codec.c uses property_append() to walk the entire linked list for each property added by decode_buf_properties(). A remote unauthenticated client can supply a PUBLISH or SUBSCRIBE packet containing many User Properties, causing O(N²) linked-list insertion and CPU work that makes the broker unresponsive; repeated packets can sustain the denial of service. This issue is fixed in version 0.24.14."}],"affected":[{"vendor":"nanomq","product":"nanomq","versions":[{"version":"< 0.24.14","status":"affected"}]}],"references":[{"url":"https://github.com/nanomq/nanomq/security/advisories/GHSA-6mwg-445v-2qrv","name":"https://github.com/nanomq/nanomq/security/advisories/GHSA-6mwg-445v-2qrv","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/nanomq/NanoNNG/pull/1508","name":"https://github.com/nanomq/NanoNNG/pull/1508","tags":["x_refsource_MISC"]},{"url":"https://github.com/nanomq/NanoNNG/commit/91bd4c7f45f945a3f5f0e37c459157dc7c277a07","name":"https://github.com/nanomq/NanoNNG/commit/91bd4c7f45f945a3f5f0e37c459157dc7c277a07","tags":["x_refsource_MISC"]},{"url":"https://github.com/nanomq/nanomq/releases/tag/0.24.14","name":"https://github.com/nanomq/nanomq/releases/tag/0.24.14","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":3.7,"baseSeverity":"LOW","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-407","lang":"en","description":"CWE-407: Inefficient Algorithmic Complexity","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-09-18T16:17:56.222Z"},"source":{"advisory":"GHSA-6mwg-445v-2qrv","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/nanomq/nanomq/security/advisories/GHSA-6mwg-445v-2qrv","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-18T17:19:13.578066Z","id":"CVE-2026-44639","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-18T17:21:50.284Z"}}]}}}