NanoMQ: O(N²) Denial of Service in MQTT v5 Property Parsing
cve-program · CVE-2026-44639
PublishedNanoMQ 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.
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cve-program · CVE-2026-44639
PublishedNanoMQ: O(N²) Denial of Service in MQTT v5 Property Parsing
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.
- Source published
- 18 Sep 2026 16:17:56 UTC
- Source modified
- 18 Sep 2026 17:21:50 UTC
- Saved here
- 23 Oct 2026 15:48:27 UTC
- Source terms
- CVE Program Terms of Use
Original source record · Cite this exact observation · Complete original publisher JSON
Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
CVSS 3.1 · 3.7 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L