{"id":"CVE-2026-61633","published":"2026-09-18T17:16:58.340","lastModified":"2026-09-18T18:17:09.433","description":"NanoMQ is an MQTT broker. Prior to 0.24.14, the NanoMQ client function nni_mqtt_msg_decode_unsubscribe() in nng/src/supplemental/mqtt/mqtt_codec.c does not handle a failed read_uint16() while counting topics in a malformed UNSUBSCRIBE packet. A zero-length topic followed by trailing data can leave buf.curpos unchanged while topic_count continues to increase, allowing a malicious MQTT broker to hang a connecting MQTT 3.1.1 client, consume CPU and memory, and repeatedly deny service when automatic reconnection is enabled. The broker-side nmq_unsubinfo_decode path is not affected. This issue is fixed in version 0.24.14.","cvssScore":2,"cvssSeverity":"LOW","cvssVector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:L","cwes":["CWE-835"],"vendors":[],"products":[],"references":[{"url":"https://github.com/nanomq/NanoNNG/commit/fa8d859bb39841e46cfc6cce280d242bd782ad3d","tags":[]},{"url":"https://github.com/nanomq/NanoNNG/pull/1518","tags":[]},{"url":"https://github.com/nanomq/nanomq/releases/tag/0.24.14","tags":[]},{"url":"https://github.com/nanomq/nanomq/security/advisories/GHSA-m7mp-rr3v-hmhr","tags":[]},{"url":"https://github.com/nanomq/nanomq/security/advisories/GHSA-m7mp-rr3v-hmhr","tags":[]}],"exploitRefs":[{"url":"https://github.com/nanomq/NanoNNG/commit/fa8d859bb39841e46cfc6cce280d242bd782ad3d","tags":[]},{"url":"https://github.com/nanomq/NanoNNG/pull/1518","tags":[]},{"url":"https://github.com/nanomq/nanomq/releases/tag/0.24.14","tags":[]},{"url":"https://github.com/nanomq/nanomq/security/advisories/GHSA-m7mp-rr3v-hmhr","tags":[]},{"url":"https://github.com/nanomq/nanomq/security/advisories/GHSA-m7mp-rr3v-hmhr","tags":[]}],"hasPoc":true,"ai":null}