CVE-2026-32134
In versions 0.24.10 and below, when NanoMQ handles high-concurrency reconnect traffic using a reconnect-collision payload, the broker can crash due to a NULL pointer dereference during MQTT session resumption for clean_start=0 clients.
Does this matter?
Lower severity and a low EPSS score (0.40%). Track it; it rarely justifies an emergency change on its own.
Description
NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. In versions 0.24.10 and below, when NanoMQ handles high-concurrency reconnect traffic using a reconnect-collision payload, the broker can crash due to a NULL pointer dereference during MQTT session resumption for clean_start=0 clients. The transport's p_peer callback (tcptran_pipe_peer()) iterates cpipe->subinfol while copying session metadata from the cached old pipe to the new reconnecting pipe, without checking whether the pointer is NULL. Under a reconnect race, cpipe->subinfol can be freed and set to NULL before session restore invokes this function, resulting in a remote unauthenticated Denial-of-Service (process crash) condition. This issue has been fixed in version 0.24.11.
- CVSS 3.1
- 5.9 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.40% probability · 34th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Source
- security-advisories@github.com
References
- https://github.com/nanomq/NanoNNG/commit/522ec62e29e60d1122f2aedaa6e702dcf089f7bb
- https://github.com/nanomq/nanomq/issues/2241
- https://github.com/nanomq/nanomq/releases/tag/0.24.11
- https://github.com/nanomq/nanomq/security/advisories/GHSA-q36f-83mh-pcv2
- https://github.com/nanomq/nanomq/issues/2241
- https://github.com/nanomq/nanomq/security/advisories/GHSA-q36f-83mh-pcv2
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.