Use After Free in Emqx Nanomq
CVE-2026-22040
NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. In version 0.24.6, by generating a combined traffic pattern of high-frequency publishes and rapid reconnect/kick-out using the same ClientID and massive subscribe/unsubscribe jitter, it is possible to reliably trigger heap memory corruption in the Broker process, causing it to exit immediately with SIGABRT due to free(): invalid pointer. As of time of publication, no known patched versions are available.
Vulnerability class: Use-After-Free
EPSS: 0.002 (12.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H.
Affected products
- Emqx Nanomq
- Nanomq — versions = 0.24.6
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-22040?
- CVE-2026-22040 is a medium-severity vulnerability in Emqx Nanomq, classified under Use After Free. CVSS score: 5.3/10. Published 2026-03-04.
- How severe is CVE-2026-22040?
- Medium severity. CVSS v3 base score is 5.3 out of 10.